diff --git a/packages/pyright-internal/src/analyzer/typeEvaluator.ts b/packages/pyright-internal/src/analyzer/typeEvaluator.ts
index ab0e17245..9c549cd0e 100644
--- a/packages/pyright-internal/src/analyzer/typeEvaluator.ts
+++ b/packages/pyright-internal/src/analyzer/typeEvaluator.ts
@@ -20050,6 +20050,12 @@ export function createTypeEvaluator(
                         addError(LocMessage.protocolNotAllowed(), errorNode);
                     }
 
+                    typeArgs?.forEach((typeArg) => {
+                        if (typeArg.typeList || !isTypeVar(typeArg.type)) {
+                            addError(LocMessage.protocolTypeArgMustBeTypeParam(), typeArg.node);
+                        }
+                    });
+
                     return {
                         type: createSpecialType(
                             classType,
diff --git a/packages/pyright-internal/src/localization/localize.ts b/packages/pyright-internal/src/localization/localize.ts
index c0d0d9876..06c94d41f 100644
--- a/packages/pyright-internal/src/localization/localize.ts
+++ b/packages/pyright-internal/src/localization/localize.ts
@@ -811,6 +811,7 @@ export namespace Localizer {
         export const protocolBaseClassWithTypeArgs = () => getRawString('Diagnostic.protocolBaseClassWithTypeArgs');
         export const protocolIllegal = () => getRawString('Diagnostic.protocolIllegal');
         export const protocolNotAllowed = () => getRawString('Diagnostic.protocolNotAllowed');
+        export const protocolTypeArgMustBeTypeParam = () => getRawString('Diagnostic.protocolTypeArgMustBeTypeParam');
         export const protocolUnsafeOverlap = () =>
             new ParameterizedString<{ name: string }>(getRawString('Diagnostic.protocolUnsafeOverlap'));
         export const protocolVarianceContravariant = () =>
diff --git a/packages/pyright-internal/src/localization/package.nls.en-us.json b/packages/pyright-internal/src/localization/package.nls.en-us.json
index 4bbd301f1..f12de1f81 100644
--- a/packages/pyright-internal/src/localization/package.nls.en-us.json
+++ b/packages/pyright-internal/src/localization/package.nls.en-us.json
@@ -389,6 +389,7 @@
         "protocolBaseClassWithTypeArgs": "Type arguments are not allowed with Protocol class when using type parameter syntax",
         "protocolIllegal": "Use of \"Protocol\" requires Python 3.7 or newer",
         "protocolNotAllowed": "\"Protocol\" cannot be used in this context",
+        "protocolTypeArgMustBeTypeParam": "Type argument for \"Protocol\" must be a type parameter",
         "protocolUnsafeOverlap": "Class overlaps \"{name}\" unsafely and could produce a match at runtime",
         "protocolVarianceContravariant": "Type variable \"{variable}\" used in generic protocol \"{class}\" should be contravariant",
         "protocolVarianceCovariant": "Type variable \"{variable}\" used in generic protocol \"{class}\" should be covariant",
diff --git a/packages/pyright-internal/src/tests/samples/protocol1.py b/packages/pyright-internal/src/tests/samples/protocol1.py
index 5d190da5e..ccf66cada 100644
--- a/packages/pyright-internal/src/tests/samples/protocol1.py
+++ b/packages/pyright-internal/src/tests/samples/protocol1.py
@@ -1,6 +1,6 @@
 # This sample tests the type checker's handling of generic protocol types.
 
-from typing import Generic, TypeVar, Protocol
+from typing import Generic, Protocol, TypeVar
 
 T = TypeVar("T")
 T_co = TypeVar("T_co", covariant=True)
@@ -8,13 +8,11 @@ T_contra = TypeVar("T_contra", contravariant=True)
 
 
 class Box(Protocol[T_co]):
-    def content(self) -> T_co:
-        ...
+    def content(self) -> T_co: ...
 
 
 class Box_Impl:
-    def content(self) -> int:
-        ...
+    def content(self) -> int: ...
 
 
 box: Box[float]
@@ -25,13 +23,11 @@ box = second_box
 
 
 class Sender(Protocol[T_contra]):
-    def send(self, data: T_contra) -> int:
-        ...
+    def send(self, data: T_contra) -> int: ...
 
 
 class Sender_Impl:
-    def send(self, data: float) -> int:
-        ...
+    def send(self, data: float) -> int: ...
 
 
 sender: Sender[float] = Sender_Impl()
@@ -77,8 +73,7 @@ var2: list[Protocol] = []
 
 
 class Abstract1(Protocol[T_contra]):
-    def do(self, x: T_contra | None):
-        ...
+    def do(self, x: T_contra | None): ...
 
 
 class Concrete1:
@@ -95,34 +90,28 @@ use_protocol1(Concrete1())
 
 # This should generate an error because TypeVars cannot
 # be defined in both Protocol and Generic.
-class Proto2(Protocol[T_co], Generic[T_co]):
-    ...
+class Proto2(Protocol[T_co], Generic[T_co]): ...
 
 
-class Proto3(Protocol, Generic[T_co]):
-    ...
+class Proto3(Protocol, Generic[T_co]): ...
 
 
 _A = TypeVar("_A", covariant=True)
 _B = TypeVar("_B", covariant=True, bound=int)
 
 
-class ProtoBase1(Protocol[_A, _B]):
-    ...
+class ProtoBase1(Protocol[_A, _B]): ...
 
 
 # This should generate an error because Protocol must
 # include all of the TypeVars.
-class Proto4(ProtoBase1[_A, _B], Protocol[_A]):
-    ...
+class Proto4(ProtoBase1[_A, _B], Protocol[_A]): ...
 
 
-class ProtoBase2(Protocol[_B]):
-    ...
+class ProtoBase2(Protocol[_B]): ...
 
 
-class Proto5(ProtoBase2[_B], Protocol[_A, _B]):
-    ...
+class Proto5(ProtoBase2[_B], Protocol[_A, _B]): ...
 
 
 p5_1: Proto5[float, int]
@@ -141,3 +130,8 @@ def func1():
 # This should generate an error because Protocol isn't
 # allowed in a TypeVar bound.
 T = TypeVar("T", bound=Protocol | int)
+
+
+# This should generate an error because int is not a TypeVar
+class Proto6(Protocol[int]):
+    pass
diff --git a/packages/pyright-internal/src/tests/typeEvaluator7.test.ts b/packages/pyright-internal/src/tests/typeEvaluator7.test.ts
index fdb201919..056c437fa 100644
--- a/packages/pyright-internal/src/tests/typeEvaluator7.test.ts
+++ b/packages/pyright-internal/src/tests/typeEvaluator7.test.ts
@@ -286,7 +286,7 @@ test('GenericType45', () => {
 test('Protocol1', () => {
     const analysisResults = TestUtils.typeAnalyzeSampleFiles(['protocol1.py']);
 
-    TestUtils.validateResults(analysisResults, 8);
+    TestUtils.validateResults(analysisResults, 9);
 });
 
 test('Protocol2', () => {