diff --git a/packages/OS400/initscript.sh b/packages/OS400/initscript.sh
index df6bf49b6d..9bf93a8e64 100644
--- a/packages/OS400/initscript.sh
+++ b/packages/OS400/initscript.sh
@@ -40,7 +40,7 @@ TGTCCSID='500'                  # Target CCSID of objects
 DEBUG='*ALL'                    # Debug level
 OPTIMIZE='10'                   # Optimisation level
 OUTPUT='*NONE'                  # Compilation output option.
-TGTRLS='V5R2M0'                 # Target OS release
+TGTRLS='V5R3M0'                 # Target OS release
 
 export TARGETLIB STATBNDDIR DYNBNDDIR SRVPGM TGTCCSID DEBUG OPTIMIZE OUTPUT
 export TGTRLS