diff --git a/BaseTools/Source/Python/GenFds/GenFdsGlobalVariable.py b/BaseTools/Source/Python/GenFds/GenFdsGlobalVariable.py
index e867693d7c..ea61f723a7 100644
--- a/BaseTools/Source/Python/GenFds/GenFdsGlobalVariable.py
+++ b/BaseTools/Source/Python/GenFds/GenFdsGlobalVariable.py
@@ -574,9 +574,9 @@ class GenFdsGlobalVariable:
         if BaseAddress:
             Cmd += ("-r", BaseAddress)
 
-        if not ForceRebase:
+        if ForceRebase == False:
             Cmd += ("-F", "FALSE")
-        else:
+        elif ForceRebase == True:
             Cmd += ("-F", "TRUE")
 
         if Capsule: