diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 220a581af..4a8fb5fb6 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -9,6 +9,12 @@ Changelog
 0.21
 ====
 
+0.21.1
+------
+Fixed
+^^^^^
+- Fix error on using old style `pk=True`
+
 0.21.0
 ------
 Added
diff --git a/pyproject.toml b/pyproject.toml
index f49a2c19e..0281ea0e6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "tortoise-orm"
-version = "0.21.0"
+version = "0.21.1"
 description = "Easy async ORM for python, built with relations in mind"
 authors = ["Andrey Bondar <andrey@bondar.ru>", "Nickolas Grigoriadis <nagrigoriadis@gmail.com>", "long2ice <long2ice@gmail.com>"]
 license = "Apache-2.0"
diff --git a/tests/test_basic.py b/tests/test_basic.py
index c6491badd..189897776 100644
--- a/tests/test_basic.py
+++ b/tests/test_basic.py
@@ -1,4 +1,4 @@
-from tests.testmodels import Tournament
+from tests.testmodels import OldStyleModel, Tournament
 from tortoise.contrib import test
 
 
@@ -10,7 +10,8 @@ async def test_basic(self):
         self.assertEqual(saved_event.id, tournament.id)
         await Tournament(name="Test 2").save()
         self.assertEqual(
-            await Tournament.all().values_list("id", flat=True), [tournament.id, tournament.id + 1]
+            await Tournament.all().values_list("id", flat=True),
+            [tournament.id, tournament.id + 1],
         )
         self.assertListSortEqual(
             await Tournament.all().values("id", "name"),
@@ -20,3 +21,10 @@ async def test_basic(self):
             ],
             sorted_key="id",
         )
+
+    async def test_basic_oldstyle(self):
+        obj = await OldStyleModel.create(name="Test")
+        assert obj.pk
+
+        assert OldStyleModel._meta.fields_map["id"].pk
+        assert OldStyleModel._meta.fields_map["name"].index
diff --git a/tests/testmodels.py b/tests/testmodels.py
index a1021096c..e6ac6d87f 100644
--- a/tests/testmodels.py
+++ b/tests/testmodels.py
@@ -868,6 +868,11 @@ class Pair(Model):
     )
 
 
+class OldStyleModel(Model):
+    id = fields.IntField(pk=True)
+    name = fields.CharField(max_length=255, index=True)
+
+
 def camelize_var(var_name: str):
     var_parts: List[str] = var_name.split("_")
     return var_parts[0] + "".join([part.title() for part in var_parts[1:]])
diff --git a/tortoise/fields/data.py b/tortoise/fields/data.py
index 7343c6437..af16c6b5b 100644
--- a/tortoise/fields/data.py
+++ b/tortoise/fields/data.py
@@ -74,7 +74,7 @@ class IntField(Field[int], int):
     allows_generated = True
 
     def __init__(self, primary_key: Optional[bool] = None, **kwargs: Any) -> None:
-        if primary_key:
+        if primary_key or kwargs.get("pk"):
             kwargs["generated"] = bool(kwargs.get("generated", True))
         super().__init__(primary_key=primary_key, **kwargs)
 
@@ -113,7 +113,7 @@ class BigIntField(Field[int], int):
     allows_generated = True
 
     def __init__(self, primary_key: Optional[bool] = None, **kwargs: Any) -> None:
-        if primary_key:
+        if primary_key or kwargs.get("pk"):
             kwargs["generated"] = bool(kwargs.get("generated", True))
         super().__init__(primary_key=primary_key, **kwargs)
 
@@ -153,7 +153,7 @@ class SmallIntField(Field[int], int):
     allows_generated = True
 
     def __init__(self, primary_key: Optional[bool] = None, **kwargs: Any) -> None:
-        if primary_key:
+        if primary_key or kwargs.get("pk"):
             kwargs["generated"] = bool(kwargs.get("generated", True))
         super().__init__(primary_key=primary_key, **kwargs)