diff --git a/CHANGES b/CHANGES
index 48ae4db57..c96659a84 100644
--- a/CHANGES
+++ b/CHANGES
@@ -155,6 +155,7 @@ Features added
 
 * #4182: autodoc: Support :confval:`suppress_warnings`
 * #5533: autodoc: :confval:`autodoc_default_options` supports ``member-order``
+* #5394: autodoc: Display readable names in type annotations for mocked objects
 * #4018: htmlhelp: Add :confval:`htmlhelp_file_suffix` and
   :confval:`htmlhelp_link_suffix`
 * #5559: text: Support complex tables (colspan and rowspan)
diff --git a/sphinx/ext/autodoc/importer.py b/sphinx/ext/autodoc/importer.py
index 55e4ce6cc..f19464b13 100644
--- a/sphinx/ext/autodoc/importer.py
+++ b/sphinx/ext/autodoc/importer.py
@@ -32,13 +32,18 @@ logger = logging.getLogger(__name__)
 class _MockObject:
     """Used by autodoc_mock_imports."""
 
+    __display_name__ = '_MockObject'
+
     def __new__(cls, *args, **kwargs):
         # type: (Any, Any) -> Any
-        if len(args) == 3 and isinstance(args[1], tuple) and args[1][-1].__class__ is cls:
-            # subclassing MockObject
-            return type(args[0], (_MockObject,), args[2], **kwargs)  # type: ignore
-        else:
-            return super(_MockObject, cls).__new__(cls)
+        if len(args) == 3 and isinstance(args[1], tuple):
+            superclass = args[1][-1].__class__
+            if superclass is cls:
+                # subclassing MockObject
+                return _make_subclass(args[0], superclass.__display_name__,
+                                      superclass=superclass, attributes=args[2])
+
+        return super(_MockObject, cls).__new__(cls)
 
     def __init__(self, *args, **kwargs):
         # type: (Any, Any) -> None
@@ -62,11 +67,11 @@ class _MockObject:
 
     def __getitem__(self, key):
         # type: (str) -> _MockObject
-        return self
+        return _make_subclass(key, self.__display_name__, self.__class__)()
 
     def __getattr__(self, key):
         # type: (str) -> _MockObject
-        return self
+        return _make_subclass(key, self.__display_name__, self.__class__)()
 
     def __call__(self, *args, **kw):
         # type: (Any, Any) -> Any
@@ -75,6 +80,18 @@ class _MockObject:
             return args[0]
         return self
 
+    def __repr__(self):
+        # type: () -> str
+        return self.__display_name__
+
+
+def _make_subclass(name, module, superclass=_MockObject, attributes=None):
+    # type: (str, str, Any, dict) -> Any
+    attrs = {'__module__': module, '__display_name__': module + '.' + name}
+    attrs.update(attributes or {})
+
+    return type(name, (superclass,), attrs)
+
 
 class _MockModule(ModuleType):
     """Used by autodoc_mock_imports."""
@@ -92,9 +109,11 @@ class _MockModule(ModuleType):
 
     def __getattr__(self, name):
         # type: (str) -> _MockObject
-        o = _MockObject()
-        o.__module__ = self.__name__
-        return o
+        return _make_subclass(name, self.__name__)()
+
+    def __repr__(self):
+        # type: () -> str
+        return self.__name__
 
 
 class _MockImporter(MetaPathFinder):
diff --git a/tests/roots/test-ext-autodoc/target/need_mocks.py b/tests/roots/test-ext-autodoc/target/need_mocks.py
index 4f83579a4..b8a661581 100644
--- a/tests/roots/test-ext-autodoc/target/need_mocks.py
+++ b/tests/roots/test-ext-autodoc/target/need_mocks.py
@@ -15,6 +15,11 @@ def decoratedFunction():
     return None
 
 
+def func(arg: missing_module.Class):
+    """a function takes mocked object as an argument"""
+    pass
+
+
 class TestAutodoc(object):
     """TestAutodoc docstring."""
     @missing_name
diff --git a/tests/test_autodoc.py b/tests/test_autodoc.py
index a25a13639..a56226b42 100644
--- a/tests/test_autodoc.py
+++ b/tests/test_autodoc.py
@@ -1345,7 +1345,7 @@ def test_autofunction_for_callable(app):
 @pytest.mark.sphinx('html', testroot='ext-autodoc')
 def test_mocked_module_imports(app, warning):
     # no autodoc_mock_imports
-    options = {"members": 'TestAutodoc,decoratedFunction'}
+    options = {"members": 'TestAutodoc,decoratedFunction,func'}
     actual = do_autodoc(app, 'module', 'target.need_mocks', options)
     assert list(actual) == []
     assert "autodoc: failed to import module 'need_mocks'" in warning.getvalue()
@@ -1382,6 +1382,12 @@ def test_mocked_module_imports(app, warning):
         '   :module: target.need_mocks',
         '',
         '   decoratedFunction docstring',
+        '   ',
+        '',
+        '.. py:function:: func(arg: missing_module.Class)',
+        '   :module: target.need_mocks',
+        '',
+        '   a function takes mocked object as an argument',
         '   '
     ]
     assert warning.getvalue() == ''
diff --git a/tests/test_ext_autodoc_importer.py b/tests/test_ext_autodoc_importer.py
index ea40632ef..08920cc7e 100644
--- a/tests/test_ext_autodoc_importer.py
+++ b/tests/test_ext_autodoc_importer.py
@@ -16,6 +16,21 @@ import pytest
 from sphinx.ext.autodoc.importer import _MockModule, _MockObject, mock
 
 
+def test_MockModule():
+    mock = _MockModule('mocked_module', None)
+    assert isinstance(mock.some_attr, _MockObject)
+    assert isinstance(mock.some_method, _MockObject)
+    assert isinstance(mock.attr1.attr2, _MockObject)
+    assert isinstance(mock.attr1.attr2.meth(), _MockObject)
+
+    assert repr(mock.some_attr) == 'mocked_module.some_attr'
+    assert repr(mock.some_method) == 'mocked_module.some_method'
+    assert repr(mock.attr1.attr2) == 'mocked_module.attr1.attr2'
+    assert repr(mock.attr1.attr2.meth) == 'mocked_module.attr1.attr2.meth'
+
+    assert repr(mock) == 'mocked_module'
+
+
 def test_MockObject():
     mock = _MockObject()
     assert isinstance(mock.some_attr, _MockObject)
@@ -25,6 +40,7 @@ def test_MockObject():
 
     class SubClass(mock.SomeClass):
         """docstring of SubClass"""
+
         def method(self):
             return "string"