diff --git a/OptionRomPkg/Application/BltLibSample/BltLibSample.c b/OptionRomPkg/Application/BltLibSample/BltLibSample.c
index 300b9ee117..29f270c3f4 100644
--- a/OptionRomPkg/Application/BltLibSample/BltLibSample.c
+++ b/OptionRomPkg/Application/BltLibSample/BltLibSample.c
@@ -40,7 +40,7 @@ Rand32 (
   )
 {
   UINTN    Found;
-  UINTN    Bits;
+  INTN     Bits;
   UINT64   Tsc1;
   UINT64   Tsc2;
   UINT64   TscBits;
diff --git a/OptionRomPkg/Library/FrameBufferBltLib/FrameBufferBltLib.c b/OptionRomPkg/Library/FrameBufferBltLib/FrameBufferBltLib.c
index cfd5212d48..2df840af15 100644
--- a/OptionRomPkg/Library/FrameBufferBltLib/FrameBufferBltLib.c
+++ b/OptionRomPkg/Library/FrameBufferBltLib/FrameBufferBltLib.c
@@ -66,7 +66,7 @@ ConfigurePixelBitMaskFormat (
   MergedMasks = (UINT32) (MergedMasks | Masks[3]);
 
   ASSERT (MergedMasks != 0);
-  mBltLibBytesPerPixel = (HighBitSet32 (MergedMasks) + 7) / 8;
+  mBltLibBytesPerPixel = (UINTN) ((HighBitSet32 (MergedMasks) + 7) / 8);
 
   DEBUG ((EFI_D_INFO, "Bytes per pixel: %d\n", mBltLibBytesPerPixel));