diff --git a/runtime/syntax/c.micro b/runtime/syntax/c.micro
index 6ebfb306..035df1ca 100644
--- a/runtime/syntax/c.micro
+++ b/runtime/syntax/c.micro
@@ -21,7 +21,7 @@ color statement "[.:;,+*|=!\%]" "<" ">" "/" "-" "&"
 #Parenthetical Color
 # color magenta "[(){}]" "\[" "\]"
 
-color constant.number "\b[0-9]+\b"
+color constant.number "\b[0-9]+\b" "\b0x[0-9A-Fa-f]+\b"
 
 ##
 ## String highlighting.  You will in general want your brightblacks and