diff --git a/syntax/gas.vim b/syntax/gas.vim
index 2f76fa6..2633b60 100644
--- a/syntax/gas.vim
+++ b/syntax/gas.vim
@@ -36,6 +36,7 @@ syn keyword gasDirective	.reloc .rept .sbttl .scl .section .set .single .size .s
 syn keyword gasDirective	.stabd .stabn .stabs .struct .subsection
 syn keyword gasDirective	.symver .tag .text .title .type .uleb128 .val .version
 syn keyword gasDirective	.vtable_entry .vtable_inherit .warning .weak .weakref
+syn keyword gasDirective	.ifdef
 
 
 syn keyword gasDirectiveStore	.byte .hword .word .int .long .double .short .float .quad .octa