diff --git a/crates/swc/tests/exec/issues-6xxx/6581/1/.swcrc b/crates/swc/tests/exec/issues-6xxx/6581/1/.swcrc
new file mode 100644
index 000000000000..f3fa9a792922
--- /dev/null
+++ b/crates/swc/tests/exec/issues-6xxx/6581/1/.swcrc
@@ -0,0 +1,19 @@
+{
+    "jsc": {
+        "parser": {
+            "syntax": "typescript",
+            "tsx": true
+        },
+        "target": "es2019",
+        "loose": true,
+        "minify": {
+            "compress": false,
+            "mangle": false
+        }
+    },
+    "module": {
+        "type": "es6"
+    },
+    "minify": false,
+    "isModule": true
+}
\ No newline at end of file
diff --git a/crates/swc/tests/exec/issues-6xxx/6581/1/exec.ts b/crates/swc/tests/exec/issues-6xxx/6581/1/exec.ts
new file mode 100644
index 000000000000..65f396e5efdb
--- /dev/null
+++ b/crates/swc/tests/exec/issues-6xxx/6581/1/exec.ts
@@ -0,0 +1,9 @@
+class Hoge {
+    #hoge: number
+    constructor() {
+        this.#hoge = 42
+    }
+}
+
+new Hoge()
+new Hoge()
\ No newline at end of file
diff --git a/crates/swc/tests/exec/issues-6xxx/6581/2/.swcrc b/crates/swc/tests/exec/issues-6xxx/6581/2/.swcrc
new file mode 100644
index 000000000000..4512d3085417
--- /dev/null
+++ b/crates/swc/tests/exec/issues-6xxx/6581/2/.swcrc
@@ -0,0 +1,20 @@
+{
+    "jsc": {
+        "parser": {
+            "syntax": "typescript",
+            "tsx": true
+        },
+        "target": "es2019",
+        "loose": true,
+        "minify": {
+            "compress": false,
+            "mangle": false
+        },
+        "externalHelpers": true
+    },
+    "module": {
+        "type": "es6"
+    },
+    "minify": false,
+    "isModule": true
+}
\ No newline at end of file
diff --git a/crates/swc/tests/exec/issues-6xxx/6581/2/exec.ts b/crates/swc/tests/exec/issues-6xxx/6581/2/exec.ts
new file mode 100644
index 000000000000..65f396e5efdb
--- /dev/null
+++ b/crates/swc/tests/exec/issues-6xxx/6581/2/exec.ts
@@ -0,0 +1,9 @@
+class Hoge {
+    #hoge: number
+    constructor() {
+        this.#hoge = 42
+    }
+}
+
+new Hoge()
+new Hoge()
\ No newline at end of file
diff --git a/packages/swc-helpers/src/_class_private_field_loose_base.mjs b/packages/swc-helpers/src/_class_private_field_loose_base.mjs
index c24fda439fbc..79ca6c8ec3f9 100644
--- a/packages/swc-helpers/src/_class_private_field_loose_base.mjs
+++ b/packages/swc-helpers/src/_class_private_field_loose_base.mjs
@@ -3,5 +3,5 @@ export default function _classPrivateFieldBase(receiver, privateKey) {
     throw new TypeError("attempted to use private field on non-instance");
   }
 
-  return receiver;
+  return receiver[privateKey];
 }