diff --git a/contrib/syntax/vim/syntax/dockerfile.vim b/contrib/syntax/vim/syntax/dockerfile.vim
index 3cb1ecfddf..bb75da8581 100644
--- a/contrib/syntax/vim/syntax/dockerfile.vim
+++ b/contrib/syntax/vim/syntax/dockerfile.vim
@@ -11,7 +11,7 @@ let b:current_syntax = "dockerfile"
 
 syntax case ignore
 
-syntax match dockerfileKeyword /\v^\s*(ONBUILD\s+)?(ADD|CMD|ENTRYPOINT|ENV|EXPOSE|FROM|MAINTAINER|RUN|USER|LABEL|VOLUME|WORKDIR|COPY|STOPSIGNAL)\s/
+syntax match dockerfileKeyword /\v^\s*(ONBUILD\s+)?(ADD|CMD|ENTRYPOINT|ENV|EXPOSE|FROM|MAINTAINER|RUN|USER|LABEL|VOLUME|WORKDIR|COPY|STOPSIGNAL|ARG)\s/
 highlight link dockerfileKeyword Keyword
 
 syntax region dockerfileString start=/\v"/ skip=/\v\\./ end=/\v"/