diff --git a/src/coreclr/vm/eventpipeinternal.cpp b/src/coreclr/vm/eventpipeinternal.cpp
index 454a4bdae04e0e..4ed2b819aee42c 100644
--- a/src/coreclr/vm/eventpipeinternal.cpp
+++ b/src/coreclr/vm/eventpipeinternal.cpp
@@ -60,7 +60,7 @@ extern "C" void QCALLTYPE EventPipeInternal_Disable(UINT64 sessionID)
     END_QCALL;
 }
 
-extern "C" bool QCALLTYPE EventPipeInternal_GetSessionInfo(UINT64 sessionID, EventPipeSessionInfo *pSessionInfo)
+extern "C" BOOL QCALLTYPE EventPipeInternal_GetSessionInfo(UINT64 sessionID, EventPipeSessionInfo *pSessionInfo)
 {
     QCALL_CONTRACT;
 
@@ -229,7 +229,7 @@ extern "C" void QCALLTYPE EventPipeInternal_WriteEventData(
     END_QCALL;
 }
 
-extern "C" bool QCALLTYPE EventPipeInternal_GetNextEvent(UINT64 sessionID, EventPipeEventInstanceData *pInstance)
+extern "C" BOOL QCALLTYPE EventPipeInternal_GetNextEvent(UINT64 sessionID, EventPipeEventInstanceData *pInstance)
 {
     QCALL_CONTRACT;
 
@@ -255,7 +255,7 @@ extern "C" bool QCALLTYPE EventPipeInternal_GetNextEvent(UINT64 sessionID, Event
     return pNextInstance != NULL;
 }
 
-extern "C" bool QCALLTYPE EventPipeInternal_SignalSession(UINT64 sessionID)
+extern "C" BOOL QCALLTYPE EventPipeInternal_SignalSession(UINT64 sessionID)
 {
     QCALL_CONTRACT;
 
@@ -268,7 +268,7 @@ extern "C" bool QCALLTYPE EventPipeInternal_SignalSession(UINT64 sessionID)
     return result;
 }
 
-extern "C" bool QCALLTYPE EventPipeInternal_WaitForSessionSignal(UINT64 sessionID, INT32 timeoutMs)
+extern "C" BOOL QCALLTYPE EventPipeInternal_WaitForSessionSignal(UINT64 sessionID, INT32 timeoutMs)
 {
     QCALL_CONTRACT;
 
diff --git a/src/coreclr/vm/eventpipeinternal.h b/src/coreclr/vm/eventpipeinternal.h
index 7da96b67ea7b56..b18bfe96ff66af 100644
--- a/src/coreclr/vm/eventpipeinternal.h
+++ b/src/coreclr/vm/eventpipeinternal.h
@@ -51,7 +51,7 @@ extern "C" UINT64 QCALLTYPE EventPipeInternal_Enable(
 //!
 extern "C" void QCALLTYPE EventPipeInternal_Disable(UINT64 sessionID);
 
-extern "C" bool QCALLTYPE EventPipeInternal_GetSessionInfo(UINT64 sessionID, EventPipeSessionInfo *pSessionInfo);
+extern "C" BOOL QCALLTYPE EventPipeInternal_GetSessionInfo(UINT64 sessionID, EventPipeSessionInfo *pSessionInfo);
 
 extern "C" INT_PTR QCALLTYPE EventPipeInternal_CreateProvider(
     _In_z_ LPCWSTR providerName,
@@ -82,14 +82,14 @@ extern "C" void QCALLTYPE EventPipeInternal_WriteEventData(
     UINT32 eventDataCount,
     LPCGUID pActivityId, LPCGUID pRelatedActivityId);
 
-extern "C" bool QCALLTYPE EventPipeInternal_GetNextEvent(
+extern "C" BOOL QCALLTYPE EventPipeInternal_GetNextEvent(
     UINT64 sessionID,
     EventPipeEventInstanceData *pInstance);
 
-extern "C" bool QCALLTYPE EventPipeInternal_SignalSession(
+extern "C" BOOL QCALLTYPE EventPipeInternal_SignalSession(
     UINT64 sessionID);
 
-extern "C" bool QCALLTYPE EventPipeInternal_WaitForSessionSignal(
+extern "C" BOOL QCALLTYPE EventPipeInternal_WaitForSessionSignal(
     UINT64 sessionID,
     INT32 timeoutMs);