diff --git a/lib/rules/boolean-prop-naming.js b/lib/rules/boolean-prop-naming.js
index 6a2b828599..b34da42652 100644
--- a/lib/rules/boolean-prop-naming.js
+++ b/lib/rules/boolean-prop-naming.js
@@ -256,6 +256,18 @@ module.exports = {
       }
     }
 
+    function findTypeAnnotations(identifier, node) {
+      if (node.type === 'TSTypeLiteral') {
+        const currentNode = objectTypeAnnotations.get(identifier.name) || [];
+        currentNode.push(node);
+        objectTypeAnnotations.set(identifier.name, currentNode);
+      } else if (node.type === 'TSIntersectionType' || node.type === 'TSUnionType') {
+        node.types.forEach((type) => {
+          findTypeAnnotations(identifier, type);
+        });
+      }
+    }
+
     // --------------------------------------------------------------------------
     // Public
     // --------------------------------------------------------------------------
@@ -327,17 +339,7 @@ module.exports = {
       },
 
       TSTypeAliasDeclaration(node) {
-        if (node.typeAnnotation.type === 'TSTypeLiteral') {
-          objectTypeAnnotations.set(node.id.name, node.typeAnnotation);
-        } else if (node.typeAnnotation.type === 'TSIntersectionType') {
-          node.typeAnnotation.types.forEach((type) => {
-            if (type.type === 'TSTypeLiteral') {
-              const currentNode = objectTypeAnnotations.get(node.id.name) || [];
-              currentNode.push(type);
-              objectTypeAnnotations.set(node.id.name, currentNode);
-            }
-          });
-        }
+        findTypeAnnotations(node.id, node.typeAnnotation);
       },
 
       // eslint-disable-next-line object-shorthand
diff --git a/tests/lib/rules/boolean-prop-naming.js b/tests/lib/rules/boolean-prop-naming.js
index 5d46a63f2c..2e2be01e5d 100644
--- a/tests/lib/rules/boolean-prop-naming.js
+++ b/tests/lib/rules/boolean-prop-naming.js
@@ -467,6 +467,36 @@ ruleTester.run('boolean-prop-naming', rule, {
       features: ['types'],
       errors: [],
     },
+    {
+      code: `
+        type Props = {
+          isEnabled: boolean
+        } | {
+          hasLOL: boolean
+        }
+
+        const HelloNew = (props: Props) => { return <div /> };
+      `,
+      options: [{ rule: '^(is|has)[A-Z]([A-Za-z0-9]?)+' }],
+      features: ['types'],
+      errors: [],
+    },
+    {
+      code: `
+        type Props = {
+          isEnabled: boolean
+        } & ({
+          hasLOL: boolean
+        } | {
+          isLOL: boolean
+        })
+
+        const HelloNew = (props: Props) => { return <div /> };
+      `,
+      options: [{ rule: '^(is|has)[A-Z]([A-Za-z0-9]?)+' }],
+      features: ['types'],
+      errors: [],
+    },
   ]),
 
   invalid: parsers.all([
@@ -1168,5 +1198,46 @@ ruleTester.run('boolean-prop-naming', rule, {
         },
       ],
     },
+    {
+      code: `
+        type Props = {
+          enabled: boolean
+        } | {
+          hasLOL: boolean
+        }
+
+        const HelloNew = (props: Props) => { return <div /> };
+      `,
+      options: [{ rule: '^(is|has)[A-Z]([A-Za-z0-9]?)+' }],
+      features: ['types', 'no-ts-old'],
+      errors: [
+        {
+          message: 'Prop name (enabled) doesn\'t match rule (^(is|has)[A-Z]([A-Za-z0-9]?)+)',
+        },
+      ],
+    },
+    {
+      code: `
+        type Props = {
+          enabled: boolean
+        } & ({
+          hasLOL: boolean
+        } | {
+          lol: boolean
+        })
+
+        const HelloNew = (props: Props) => { return <div /> };
+      `,
+      options: [{ rule: '^(is|has)[A-Z]([A-Za-z0-9]?)+' }],
+      features: ['types', 'no-ts-old'],
+      errors: [
+        {
+          message: 'Prop name (enabled) doesn\'t match rule (^(is|has)[A-Z]([A-Za-z0-9]?)+)',
+        },
+        {
+          message: 'Prop name (lol) doesn\'t match rule (^(is|has)[A-Z]([A-Za-z0-9]?)+)',
+        },
+      ],
+    },
   ]),
 });