diff --git a/MdePkg/Include/Library/PcdLib.h b/MdePkg/Include/Library/PcdLib.h
index 4e2399a565..71034716c8 100644
--- a/MdePkg/Include/Library/PcdLib.h
+++ b/MdePkg/Include/Library/PcdLib.h
@@ -1171,7 +1171,7 @@ EFIAPI
 LibPcdSetPtr (
   IN        UINTN             TokenNumber,
   IN OUT    UINTN             *SizeOfBuffer,
-  IN        VOID              *Buffer
+  IN CONST  VOID              *Buffer
   );
 
 
diff --git a/MdePkg/Library/BasePcdLibNull/PcdLib.c b/MdePkg/Library/BasePcdLibNull/PcdLib.c
index 1688034263..20031ee570 100644
--- a/MdePkg/Library/BasePcdLibNull/PcdLib.c
+++ b/MdePkg/Library/BasePcdLibNull/PcdLib.c
@@ -483,7 +483,7 @@ EFIAPI
 LibPcdSetPtr (
   IN       UINTN             TokenNumber,
   IN OUT   UINTN             *SizeOfBuffer,
-  IN       VOID              *Buffer
+  IN CONST VOID              *Buffer
   )
 {
   ASSERT (FALSE);
diff --git a/MdePkg/Library/DxePcdLib/DxePcdLib.c b/MdePkg/Library/DxePcdLib/DxePcdLib.c
index e5d05fbe8c..c313bb7687 100644
--- a/MdePkg/Library/DxePcdLib/DxePcdLib.c
+++ b/MdePkg/Library/DxePcdLib/DxePcdLib.c
@@ -529,7 +529,7 @@ EFIAPI
 LibPcdSetPtr (
   IN        UINTN             TokenNumber,
   IN OUT    UINTN             *SizeOfBuffer,
-  IN        VOID              *Buffer
+  IN CONST  VOID              *Buffer
   )
 {
   EFI_STATUS Status;
@@ -540,13 +540,13 @@ LibPcdSetPtr (
     ASSERT (Buffer != NULL);
   }
 
-  Status = mPcd->SetPtr (TokenNumber, SizeOfBuffer, Buffer);
+  Status = mPcd->SetPtr (TokenNumber, SizeOfBuffer, (VOID *) Buffer);
 
   if (EFI_ERROR (Status)) {
     return NULL;
   }
 
-  return Buffer;
+  return (VOID *) Buffer;
 }
 
 
diff --git a/MdePkg/Library/PeiPcdLib/PeiPcdLib.c b/MdePkg/Library/PeiPcdLib/PeiPcdLib.c
index 8f9b7fa64e..ac5bbcf058 100644
--- a/MdePkg/Library/PeiPcdLib/PeiPcdLib.c
+++ b/MdePkg/Library/PeiPcdLib/PeiPcdLib.c
@@ -524,7 +524,7 @@ EFIAPI
 LibPcdSetPtr (
   IN       UINTN             TokenNumber,
   IN OUT   UINTN             *SizeOfBuffer,
-  IN       VOID              *Buffer
+  IN CONST VOID              *Buffer
   )
 {
   EFI_STATUS Status;
@@ -535,13 +535,13 @@ LibPcdSetPtr (
     ASSERT (Buffer != NULL);
   }
   
-  Status = (GetPcdPpiPointer ())->SetPtr (TokenNumber, SizeOfBuffer, Buffer);
+  Status = (GetPcdPpiPointer ())->SetPtr (TokenNumber, SizeOfBuffer, (VOID *) Buffer);
 
   if (EFI_ERROR (Status)) {
     return NULL;
   }
 
-  return Buffer;
+  return (VOID *) Buffer;
 }