diff --git a/voluptuous/schema_builder.py b/voluptuous/schema_builder.py
index 3673e86..5f28d90 100644
--- a/voluptuous/schema_builder.py
+++ b/voluptuous/schema_builder.py
@@ -828,6 +828,10 @@ def _compile_scalar(schema):
     if inspect.isclass(schema):
 
         def validate_instance(path, data):
+            # bool is a subclass of int; reject so True/False are not valid ints
+            if schema is int and isinstance(data, bool):
+                msg = 'expected %s' % schema.__name__
+                raise er.TypeInvalid(msg, path)
             if isinstance(data, schema):
                 return data
             else:
diff --git a/voluptuous/tests/tests.py b/voluptuous/tests/tests.py
index 0608548..98220c7 100644
--- a/voluptuous/tests/tests.py
+++ b/voluptuous/tests/tests.py
@@ -2375,3 +2375,20 @@ def test_complex_required_keys_with_specific_value_validation():
     error_msg = str(exc_info.value)
     assert "required" not in error_msg.lower()  # No "required field missing" error
     assert "value must be at most 100" in error_msg  # Range validation error
+
+
+def test_boolean_is_not_an_integer():
+    """bool is a subclass of int; Schema(int) must still reject True/False."""
+    schema = Schema(int)
+    with pytest.raises(MultipleInvalid):
+        schema(True)
+    with pytest.raises(MultipleInvalid):
+        schema(False)
+    assert schema(0) == 0
+    assert schema(1) == 1
+    with pytest.raises(MultipleInvalid):
+        Schema({'age': int})({'age': True})
+    with pytest.raises(MultipleInvalid):
+        Schema(ExactSequence([int, int]))([True, False])
+    assert Schema(bool)(True) is True
+    assert Schema(bool)(False) is False