diff --git a/add-patch.c b/add-patch.c
index f899389e2c..e6fa10715d 100644
--- a/add-patch.c
+++ b/add-patch.c
@@ -1624,7 +1624,7 @@ soft_increment:
 					 NULL, 0, NULL, 0))
 				error(_("'git apply' failed"));
 		}
-		if (!repo_read_index(s->s.r))
+		if (repo_read_index(s->s.r) >= 0)
 			repo_refresh_and_write_index(s->s.r, REFRESH_QUIET, 0,
 						     1, NULL, NULL, NULL);
 	}
diff --git a/t/t3701-add-interactive.sh b/t/t3701-add-interactive.sh
index 49decbac71..f0a491ade1 100755
--- a/t/t3701-add-interactive.sh
+++ b/t/t3701-add-interactive.sh
@@ -560,6 +560,13 @@ test_expect_success 'patch mode ignores unmerged entries' '
 	diff_cmp expected diff
 '
 
+test_expect_success 'index is refreshed after applying patch' '
+	git reset --hard &&
+	echo content >test &&
+	printf y | git add -p &&
+	git diff-files --exit-code
+'
+
 test_expect_success 'diffs can be colorized' '
 	git reset --hard &&