diff --git a/CHANGELOG.md b/CHANGELOG.md
index a3eb8ee..bb29b39 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,13 @@
 
 ## Next Release
 
+## (2025-08-14)
+
+### Fixes
+
+- fix: Ensure `object_pk` lookup works for non-string primary keys by casting PK to    string in `get_for_object()` and related queries.
+- fix: Updated tests to correctly match log entries for integer, UUID, or string  primary keys.  ([#746](https://github.com/jazzband/django-auditlog/pull/746))
+
 #### Improvements
 
 - feat: Add `AUDITLOG_USE_FK_STRING_REPRESENTATION` setting that controls how foreign key changes are represented ([#779)](https://github.com/jazzband/django-auditlog/pull/779))
diff --git a/auditlog/mixins.py b/auditlog/mixins.py
index 8ae203c..031ffd5 100644
--- a/auditlog/mixins.py
+++ b/auditlog/mixins.py
@@ -4,6 +4,7 @@ from django import urls as urlresolvers
 from django.conf import settings
 from django.contrib import admin
 from django.contrib.admin.views.main import PAGE_VAR
+from django.contrib.contenttypes.models import ContentType
 from django.core.exceptions import PermissionDenied
 from django.http import HttpRequest
 from django.template.response import TemplateResponse
@@ -139,9 +140,11 @@ class AuditlogHistoryAdminMixin:
         obj = self.get_object(request, unquote(object_id))
         if not self.has_view_permission(request, obj):
             raise PermissionDenied
-
+        ct = ContentType.objects.get_for_model(obj.__class__)
         log_entries = (
-            LogEntry.objects.get_for_object(obj)
+            LogEntry.objects.filter(
+                content_type=ct, object_pk=str(obj.pk)
+            )  # <--- Fixed here
             .select_related("actor")
             .order_by("-timestamp")
         )
diff --git a/auditlog/models.py b/auditlog/models.py
index edc5dd2..5479bd3 100644
--- a/auditlog/models.py
+++ b/auditlog/models.py
@@ -148,10 +148,7 @@ class LogEntryManager(models.Manager):
         content_type = ContentType.objects.get_for_model(instance.__class__)
         pk = self._get_pk_value(instance)
 
-        if isinstance(pk, int):
-            return self.filter(content_type=content_type, object_id=pk)
-        else:
-            return self.filter(content_type=content_type, object_pk=smart_str(pk))
+        return self.filter(content_type=content_type, object_pk=smart_str(pk))
 
     def get_for_objects(self, queryset):
         """
@@ -160,8 +157,7 @@ class LogEntryManager(models.Manager):
         :param queryset: The queryset to get the log entries for.
         :type queryset: QuerySet
         :return: The LogEntry objects for the objects in the given queryset.
-        :rtype: QuerySet
-        """
+        :rtype: QuerySet"""
         if not isinstance(queryset, QuerySet) or queryset.count() == 0:
             return self.none()
 
@@ -170,25 +166,14 @@ class LogEntryManager(models.Manager):
             queryset.values_list(queryset.model._meta.pk.name, flat=True)
         )
 
-        if isinstance(primary_keys[0], int):
-            return (
-                self.filter(content_type=content_type)
-                .filter(Q(object_id__in=primary_keys))
-                .distinct()
-            )
-        elif isinstance(queryset.model._meta.pk, models.UUIDField):
-            primary_keys = [smart_str(pk) for pk in primary_keys]
-            return (
-                self.filter(content_type=content_type)
-                .filter(Q(object_pk__in=primary_keys))
-                .distinct()
-            )
-        else:
-            return (
-                self.filter(content_type=content_type)
-                .filter(Q(object_pk__in=primary_keys))
-                .distinct()
-            )
+        # Always compare as strings for PostgreSQL compatibility
+        primary_keys = [smart_str(pk) for pk in primary_keys]
+
+        return (
+            self.filter(content_type=content_type)
+            .filter(Q(object_pk__in=primary_keys))
+            .distinct()
+        )
 
     def get_for_model(self, model):
         """
diff --git a/auditlog_tests/tests.py b/auditlog_tests/tests.py
index 3183015..a92634e 100644
--- a/auditlog_tests/tests.py
+++ b/auditlog_tests/tests.py
@@ -191,7 +191,7 @@ class SimpleModelTest(TestCase):
         self.delete(obj)
 
         # Check for log entries
-        qs = LogEntry.objects.filter(content_type=content_type, object_pk=pk)
+        qs = LogEntry.objects.filter(content_type=content_type, object_pk=str(pk))
         self.assertEqual(qs.count(), 1, msg="There is one log entry for 'DELETE'")
 
         history = qs.get()