diff --git a/scripts/sstate-cache-management.sh b/scripts/sstate-cache-management.sh
index 7d81daf..2d4a2a3 100755
--- a/scripts/sstate-cache-management.sh
+++ b/scripts/sstate-cache-management.sh
@@ -47,7 +47,9 @@ Options:
 
   -d, --remove-duplicated
         Remove the duplicated sstate cache files of one package, only
-        the newest one will be kept.
+        the newest one will be kept. The duplicated sstate cache files
+        of one package must have the same arch, which means sstate cache
+        files with multiple archs are not considered duplicate.
 
         Conflicts with --stamps-dir.