diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 5ea5b82d2b6..2ed230a8612 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -1467,6 +1467,7 @@ _git_log ()
 			--abbrev-commit --abbrev=
 			--relative-date --date=
 			--pretty= --format= --oneline
+			--show-signature
 			--cherry-pick
 			--graph
 			--decorate --decorate=
@@ -2344,6 +2345,7 @@ _git_show ()
 		;;
 	--*)
 		__gitcomp "--pretty= --format= --abbrev-commit --oneline
+			--show-signature
 			$__git_diff_common_options
 			"
 		return