diff --git a/packages/babel-parser/src/parser/expression.js b/packages/babel-parser/src/parser/expression.js
index 53026d24f664..7200b8d8a2cf 100644
--- a/packages/babel-parser/src/parser/expression.js
+++ b/packages/babel-parser/src/parser/expression.js
@@ -54,6 +54,7 @@ import {
   newAsyncArrowScope,
   newExpressionScope,
 } from "../util/expression-scope.js";
+import ClassScopeHandler from "../util/class-scope";
 import { Errors } from "./error";
 
 /*::
@@ -2680,6 +2681,8 @@ export default class ExpressionParser extends LValParser {
     this.prodParam.enter(paramFlags);
     const oldInModule = this.inModule;
     this.inModule = true;
+    const oldClassScope = this.classScope;
+    this.classScope = new ClassScopeHandler(this.raise.bind(this));
     const program = this.startNode<N.Program>();
     node.body = this.parseProgram(program, tt.braceR, "module");
     this.scope.exit();
@@ -2689,6 +2692,7 @@ export default class ExpressionParser extends LValParser {
     this.eat(tt.braceR);
     this.state.labels = oldLabels;
     this.state.exportedIdentifiers = oldExportedIdentifiers;
+    this.classScope = oldClassScope;
     return this.finishNode<N.ModuleExpression>(node, "ModuleExpression");
   }
 }
diff --git a/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/input.js b/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/input.js
new file mode 100644
index 000000000000..04f0c7aab135
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/input.js
@@ -0,0 +1,7 @@
+class B {
+  #p() {
+    module {
+      class C { [this.#p]; }
+    };
+  }
+}
diff --git a/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/options.json b/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/options.json
new file mode 100644
index 000000000000..5a36d4e0d5af
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/options.json
@@ -0,0 +1,9 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "moduleBlocks",
+    "classPrivateProperties",
+    "classPrivateMethods",
+    "classProperties"
+  ]
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/output.json b/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/output.json
new file mode 100644
index 000000000000..86b7e8c0c9e4
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/module-blocks/invalid-class-in-module-blocks/output.json
@@ -0,0 +1,116 @@
+{
+  "type": "File",
+  "start":0,"end":73,"loc":{"start":{"line":1,"column":0},"end":{"line":7,"column":1}},
+  "errors": [
+    "SyntaxError: Private name #p is not defined (4:22)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":73,"loc":{"start":{"line":1,"column":0},"end":{"line":7,"column":1}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ClassDeclaration",
+        "start":0,"end":73,"loc":{"start":{"line":1,"column":0},"end":{"line":7,"column":1}},
+        "id": {
+          "type": "Identifier",
+          "start":6,"end":7,"loc":{"start":{"line":1,"column":6},"end":{"line":1,"column":7},"identifierName":"B"},
+          "name": "B"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start":8,"end":73,"loc":{"start":{"line":1,"column":8},"end":{"line":7,"column":1}},
+          "body": [
+            {
+              "type": "ClassPrivateMethod",
+              "start":12,"end":71,"loc":{"start":{"line":2,"column":2},"end":{"line":6,"column":3}},
+              "static": false,
+              "key": {
+                "type": "PrivateName",
+                "start":12,"end":14,"loc":{"start":{"line":2,"column":2},"end":{"line":2,"column":4}},
+                "id": {
+                  "type": "Identifier",
+                  "start":13,"end":14,"loc":{"start":{"line":2,"column":3},"end":{"line":2,"column":4},"identifierName":"p"},
+                  "name": "p"
+                }
+              },
+              "kind": "method",
+              "id": null,
+              "generator": false,
+              "async": false,
+              "params": [],
+              "body": {
+                "type": "BlockStatement",
+                "start":17,"end":71,"loc":{"start":{"line":2,"column":7},"end":{"line":6,"column":3}},
+                "body": [
+                  {
+                    "type": "ExpressionStatement",
+                    "start":23,"end":67,"loc":{"start":{"line":3,"column":4},"end":{"line":5,"column":6}},
+                    "expression": {
+                      "type": "ModuleExpression",
+                      "start":23,"end":66,"loc":{"start":{"line":3,"column":4},"end":{"line":5,"column":5}},
+                      "body": {
+                        "type": "Program",
+                        "start":38,"end":66,"loc":{"start":{"line":4,"column":6},"end":{"line":5,"column":5}},
+                        "sourceType": "module",
+                        "interpreter": null,
+                        "body": [
+                          {
+                            "type": "ClassDeclaration",
+                            "start":38,"end":60,"loc":{"start":{"line":4,"column":6},"end":{"line":4,"column":28}},
+                            "id": {
+                              "type": "Identifier",
+                              "start":44,"end":45,"loc":{"start":{"line":4,"column":12},"end":{"line":4,"column":13},"identifierName":"C"},
+                              "name": "C"
+                            },
+                            "superClass": null,
+                            "body": {
+                              "type": "ClassBody",
+                              "start":46,"end":60,"loc":{"start":{"line":4,"column":14},"end":{"line":4,"column":28}},
+                              "body": [
+                                {
+                                  "type": "ClassProperty",
+                                  "start":48,"end":58,"loc":{"start":{"line":4,"column":16},"end":{"line":4,"column":26}},
+                                  "static": false,
+                                  "computed": true,
+                                  "key": {
+                                    "type": "MemberExpression",
+                                    "start":49,"end":56,"loc":{"start":{"line":4,"column":17},"end":{"line":4,"column":24}},
+                                    "object": {
+                                      "type": "ThisExpression",
+                                      "start":49,"end":53,"loc":{"start":{"line":4,"column":17},"end":{"line":4,"column":21}}
+                                    },
+                                    "computed": false,
+                                    "property": {
+                                      "type": "PrivateName",
+                                      "start":54,"end":56,"loc":{"start":{"line":4,"column":22},"end":{"line":4,"column":24}},
+                                      "id": {
+                                        "type": "Identifier",
+                                        "start":55,"end":56,"loc":{"start":{"line":4,"column":23},"end":{"line":4,"column":24},"identifierName":"p"},
+                                        "name": "p"
+                                      }
+                                    }
+                                  },
+                                  "value": null
+                                }
+                              ]
+                            }
+                          }
+                        ],
+                        "directives": []
+                      }
+                    }
+                  }
+                ],
+                "directives": []
+              }
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/input.js b/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/input.js
new file mode 100644
index 000000000000..3ca87a589410
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/input.js
@@ -0,0 +1,11 @@
+class B {
+  #p() {
+    module {
+      class C {
+        [this.#p];
+        #p = 3;
+      }
+    };
+  }
+}
+  
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/options.json b/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/options.json
new file mode 100644
index 000000000000..02815f98933b
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/options.json
@@ -0,0 +1,9 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "moduleBlocks",
+    "classPrivateProperties",
+    "classPrivateMethods",
+    "classProperties"
+  ]
+}
diff --git a/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/output.json b/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/output.json
new file mode 100644
index 000000000000..8f9f2543972c
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/module-blocks/valid-class-in-module-blocks/output.json
@@ -0,0 +1,136 @@
+{
+  "type": "File",
+  "start":0,"end":103,"loc":{"start":{"line":1,"column":0},"end":{"line":10,"column":1}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":103,"loc":{"start":{"line":1,"column":0},"end":{"line":10,"column":1}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ClassDeclaration",
+        "start":0,"end":103,"loc":{"start":{"line":1,"column":0},"end":{"line":10,"column":1}},
+        "id": {
+          "type": "Identifier",
+          "start":6,"end":7,"loc":{"start":{"line":1,"column":6},"end":{"line":1,"column":7},"identifierName":"B"},
+          "name": "B"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start":8,"end":103,"loc":{"start":{"line":1,"column":8},"end":{"line":10,"column":1}},
+          "body": [
+            {
+              "type": "ClassPrivateMethod",
+              "start":12,"end":101,"loc":{"start":{"line":2,"column":2},"end":{"line":9,"column":3}},
+              "static": false,
+              "key": {
+                "type": "PrivateName",
+                "start":12,"end":14,"loc":{"start":{"line":2,"column":2},"end":{"line":2,"column":4}},
+                "id": {
+                  "type": "Identifier",
+                  "start":13,"end":14,"loc":{"start":{"line":2,"column":3},"end":{"line":2,"column":4},"identifierName":"p"},
+                  "name": "p"
+                }
+              },
+              "kind": "method",
+              "id": null,
+              "generator": false,
+              "async": false,
+              "params": [],
+              "body": {
+                "type": "BlockStatement",
+                "start":17,"end":101,"loc":{"start":{"line":2,"column":7},"end":{"line":9,"column":3}},
+                "body": [
+                  {
+                    "type": "ExpressionStatement",
+                    "start":23,"end":97,"loc":{"start":{"line":3,"column":4},"end":{"line":8,"column":6}},
+                    "expression": {
+                      "type": "ModuleExpression",
+                      "start":23,"end":96,"loc":{"start":{"line":3,"column":4},"end":{"line":8,"column":5}},
+                      "body": {
+                        "type": "Program",
+                        "start":38,"end":96,"loc":{"start":{"line":4,"column":6},"end":{"line":8,"column":5}},
+                        "sourceType": "module",
+                        "interpreter": null,
+                        "body": [
+                          {
+                            "type": "ClassDeclaration",
+                            "start":38,"end":90,"loc":{"start":{"line":4,"column":6},"end":{"line":7,"column":7}},
+                            "id": {
+                              "type": "Identifier",
+                              "start":44,"end":45,"loc":{"start":{"line":4,"column":12},"end":{"line":4,"column":13},"identifierName":"C"},
+                              "name": "C"
+                            },
+                            "superClass": null,
+                            "body": {
+                              "type": "ClassBody",
+                              "start":46,"end":90,"loc":{"start":{"line":4,"column":14},"end":{"line":7,"column":7}},
+                              "body": [
+                                {
+                                  "type": "ClassProperty",
+                                  "start":56,"end":66,"loc":{"start":{"line":5,"column":8},"end":{"line":5,"column":18}},
+                                  "static": false,
+                                  "computed": true,
+                                  "key": {
+                                    "type": "MemberExpression",
+                                    "start":57,"end":64,"loc":{"start":{"line":5,"column":9},"end":{"line":5,"column":16}},
+                                    "object": {
+                                      "type": "ThisExpression",
+                                      "start":57,"end":61,"loc":{"start":{"line":5,"column":9},"end":{"line":5,"column":13}}
+                                    },
+                                    "computed": false,
+                                    "property": {
+                                      "type": "PrivateName",
+                                      "start":62,"end":64,"loc":{"start":{"line":5,"column":14},"end":{"line":5,"column":16}},
+                                      "id": {
+                                        "type": "Identifier",
+                                        "start":63,"end":64,"loc":{"start":{"line":5,"column":15},"end":{"line":5,"column":16},"identifierName":"p"},
+                                        "name": "p"
+                                      }
+                                    }
+                                  },
+                                  "value": null
+                                },
+                                {
+                                  "type": "ClassPrivateProperty",
+                                  "start":75,"end":82,"loc":{"start":{"line":6,"column":8},"end":{"line":6,"column":15}},
+                                  "static": false,
+                                  "key": {
+                                    "type": "PrivateName",
+                                    "start":75,"end":77,"loc":{"start":{"line":6,"column":8},"end":{"line":6,"column":10}},
+                                    "id": {
+                                      "type": "Identifier",
+                                      "start":76,"end":77,"loc":{"start":{"line":6,"column":9},"end":{"line":6,"column":10},"identifierName":"p"},
+                                      "name": "p"
+                                    }
+                                  },
+                                  "value": {
+                                    "type": "NumericLiteral",
+                                    "start":80,"end":81,"loc":{"start":{"line":6,"column":13},"end":{"line":6,"column":14}},
+                                    "extra": {
+                                      "rawValue": 3,
+                                      "raw": "3"
+                                    },
+                                    "value": 3
+                                  }
+                                }
+                              ]
+                            }
+                          }
+                        ],
+                        "directives": []
+                      }
+                    }
+                  }
+                ],
+                "directives": []
+              }
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file