diff --git a/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt b/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt
index 7bec4f27032b..3f2527dedf9e 100644
--- a/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt
+++ b/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt
@@ -4,6 +4,7 @@ package com.jetbrains.python.codeInsight.typing
 import com.intellij.util.containers.isNullOrEmpty
 import com.jetbrains.python.codeInsight.typing.PyTypingTypeProvider.PROTOCOL
 import com.jetbrains.python.psi.AccessDirection
+import com.jetbrains.python.psi.PyClass
 import com.jetbrains.python.psi.PyTypedElement
 import com.jetbrains.python.psi.resolve.PyResolveContext
 import com.jetbrains.python.psi.resolve.RatedResolveResult
@@ -17,6 +18,10 @@ fun isProtocol(classLikeType: PyClassLikeType, context: TypeEvalContext): Boolea
   return classLikeType.getSuperClassTypes(context).any { type -> PROTOCOL == type?.classQName }
 }
 
+fun isProtocol(cls: PyClass, context: TypeEvalContext): Boolean {
+  return cls.getSuperClassTypes(context).any { type -> PROTOCOL == type?.classQName }
+}
+
 fun matchingProtocolDefinitions(expected: PyType?, actual: PyType?, context: TypeEvalContext) = expected is PyClassLikeType &&
                                                                                                 actual is PyClassLikeType &&
                                                                                                 expected.isDefinition &&
diff --git a/python/src/com/jetbrains/python/inspections/PyAbstractClassInspection.java b/python/src/com/jetbrains/python/inspections/PyAbstractClassInspection.java
index dcb12155b567..a7533f04cd0e 100644
--- a/python/src/com/jetbrains/python/inspections/PyAbstractClassInspection.java
+++ b/python/src/com/jetbrains/python/inspections/PyAbstractClassInspection.java
@@ -8,6 +8,8 @@ import com.intellij.psi.PsiElementVisitor;
 import com.jetbrains.python.PyBundle;
 import com.jetbrains.python.PyNames;
 import com.jetbrains.python.codeInsight.override.PyOverrideImplementUtil;
+import com.jetbrains.python.codeInsight.typing.PyProtocolsKt;
+import com.jetbrains.python.codeInsight.typing.PyTypingTypeProvider;
 import com.jetbrains.python.inspections.quickfix.PyImplementMethodsQuickFix;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.types.PyClassLikeType;
@@ -43,7 +45,7 @@ public class PyAbstractClassInspection extends PyInspection {
 
     @Override
     public void visitPyClass(PyClass pyClass) {
-      if (isAbstract(pyClass)) {
+      if (isAbstract(pyClass) || PyProtocolsKt.isProtocol(pyClass, myTypeEvalContext)) {
         return;
       }
       final List<PyFunction> toImplement = PyOverrideImplementUtil.getAllSuperAbstractMethods(pyClass, myTypeEvalContext);
diff --git a/python/testData/inspections/PyAbstractClassInspection/typingProtocolSubclass.py b/python/testData/inspections/PyAbstractClassInspection/typingProtocolSubclass.py
new file mode 100644
index 000000000000..94bef853f8c3
--- /dev/null
+++ b/python/testData/inspections/PyAbstractClassInspection/typingProtocolSubclass.py
@@ -0,0 +1,118 @@
+from typing import Protocol
+from abc import abstractmethod
+
+
+# ------------------
+class MP1(Protocol):
+    name: str
+
+
+class CMP1(MP1):  # ok
+    pass
+
+
+def test_mp1(mp1: MP1):
+    pass
+
+
+test_mp1(CMP1())
+
+
+# ------------------
+class MP2(Protocol):
+    name: str = "name"
+
+
+class CMP2(MP2):  # ok
+    pass
+
+
+def test_mp2(mp2: MP2):
+    pass
+
+
+test_mp2(CMP2())
+
+
+# ------------------
+class MP3(Protocol):
+    def foo(self) -> int:
+        return 42
+
+
+class CMP3(MP3):  # ok
+    pass
+
+
+def test_mp3(mp3: MP3):
+    pass
+
+
+test_mp3(CMP3())
+
+
+# ------------------
+class MP4(Protocol):
+    def foo(self) -> int:
+        pass
+
+
+class CMP4(MP4):  # ok
+    pass
+
+
+def test_mp4(mp4: MP4):
+    pass
+
+
+test_mp4(CMP4())
+
+
+# ------------------
+class MP5(Protocol):
+    @abstractmethod
+    def foo(self) -> int:
+        raise NotImplementedError
+
+
+class <weak_warning descr="Class CMP5 must implement all abstract methods">CMP5</weak_warning>(MP5):  # fail
+    pass
+
+
+def test_mp5(mp5: MP5):
+    pass
+
+
+test_mp5(CMP5())
+
+
+# ------------------
+class MP6(Protocol):
+    @abstractmethod
+    def foo(self) -> int:
+        raise NotImplementedError
+
+
+class CMP6(MP6):  # ok
+    @abstractmethod
+    def bar(self) -> int:
+        raise NotImplementedError
+
+
+def test_mp6(mp6: MP6):
+    pass
+
+
+test_mp6(CMP6())
+
+
+# ------------------
+class MP7(Protocol):
+    @abstractmethod
+    def foo(self) -> int:
+        raise NotImplementedError
+
+
+class PMP7(MP7, Protocol):  # ok
+    def bar(self) -> int:
+        pass
\ No newline at end of file
diff --git a/python/testSrc/com/jetbrains/python/inspections/PyAbstractClassInspectionTest.java b/python/testSrc/com/jetbrains/python/inspections/PyAbstractClassInspectionTest.java
index b6d3e6ce860d..46aad9a4b54f 100644
--- a/python/testSrc/com/jetbrains/python/inspections/PyAbstractClassInspectionTest.java
+++ b/python/testSrc/com/jetbrains/python/inspections/PyAbstractClassInspectionTest.java
@@ -65,6 +65,11 @@ public class PyAbstractClassInspectionTest extends PyInspectionTestCase {
     doTest();
   }
 
+  // PY-26628
+  public void testTypingProtocolSubclass() {
+    runWithLanguageLevel(LanguageLevel.PYTHON37, this::doTest);
+  }
+
   @NotNull
   @Override
   protected Class<? extends PyInspection> getInspectionClass() {