diff --git a/packages/eslint-plugin/src/rules/no-inferrable-types.ts b/packages/eslint-plugin/src/rules/no-inferrable-types.ts
index 54823f7be39..f63beda7440 100644
--- a/packages/eslint-plugin/src/rules/no-inferrable-types.ts
+++ b/packages/eslint-plugin/src/rules/no-inferrable-types.ts
@@ -250,15 +250,19 @@ export default util.createRule<Options, MessageIds>({
       if (ignoreParameters || !node.params) {
         return;
       }
-      (
-        node.params.filter(
-          param =>
-            param.type === AST_NODE_TYPES.AssignmentPattern &&
-            param.left &&
-            param.right,
-        ) as TSESTree.AssignmentPattern[]
-      ).forEach(param => {
-        reportInferrableType(param, param.left.typeAnnotation, param.right);
+
+      node.params.forEach(param => {
+        if (param.type === AST_NODE_TYPES.TSParameterProperty) {
+          param = param.parameter;
+        }
+
+        if (
+          param.type === AST_NODE_TYPES.AssignmentPattern &&
+          param.left &&
+          param.right
+        ) {
+          reportInferrableType(param, param.left.typeAnnotation, param.right);
+        }
       });
     }
 
diff --git a/packages/eslint-plugin/tests/rules/no-inferrable-types.test.ts b/packages/eslint-plugin/tests/rules/no-inferrable-types.test.ts
index ce1b5deb277..fe91490df3e 100644
--- a/packages/eslint-plugin/tests/rules/no-inferrable-types.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-inferrable-types.test.ts
@@ -150,6 +150,13 @@ class Foo {
   a?: number = 5;
   b?: boolean = true;
   c?: string = 'foo';
+}
+      `,
+    },
+    {
+      code: `
+class Foo {
+  constructor(public a = true) {}
 }
       `,
     },
@@ -289,5 +296,33 @@ class Foo {
         },
       ],
     },
+    {
+      code: `
+class Foo {
+  constructor(public a: boolean = true) {}
+}
+      `,
+      output: `
+class Foo {
+  constructor(public a = true) {}
+}
+      `,
+      options: [
+        {
+          ignoreParameters: false,
+          ignoreProperties: false,
+        },
+      ],
+      errors: [
+        {
+          messageId: 'noInferrableType',
+          data: {
+            type: 'boolean',
+          },
+          line: 3,
+          column: 22,
+        },
+      ],
+    },
   ],
 });