diff --git a/builds/win32/setenvvar.bat b/builds/win32/setenvvar.bat
index 87b87e16ae2..8f0d672e7d2 100644
--- a/builds/win32/setenvvar.bat
+++ b/builds/win32/setenvvar.bat
@@ -16,12 +16,13 @@
 
 @echo off
 
-::set FB_PROCESSOR_ARCHITECTURE=AMD64
+:: 1. Determine target platform
+if "%Platform%"=="x86"  set FB_TARGET_PLATFORM=Win32
+if "%Platform%"=="x64"  set FB_TARGET_PLATFORM=x64
 
-:: Default target CPU architecture is the native environment
-if NOT DEFINED FB_PROCESSOR_ARCHITECTURE (
-set FB_PROCESSOR_ARCHITECTURE=%PROCESSOR_ARCHITECTURE%
-)
+:: 2.If Platform variable is not set, use PROCESSOR_ARCHITECTURE
+if "%FB_TARGET_PLATFORM%"=="Win32" set FB_PROCESSOR_ARCHITECTURE=x86
+if "%FB_TARGET_PLATFORM%"=="x64"   set FB_PROCESSOR_ARCHITECTURE=AMD64
 
 ::===============================
 ::Set up the compiler environment