diff --git a/.gitmodules b/.gitmodules
index 84033e2..8ed0233 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -70,10 +70,6 @@
 	path = examples/cpplint/simple
 	url = ssh://git@focs.ji.sjtu.edu.cn:2222/JOJ/JOJ3-examples.git
 	branch = cpplint/simple
-[submodule "examples/healthcheck/whitelistedchars-invalid"]
-	path = examples/healthcheck/whitelistedchars-invalid
-	url = ssh://git@focs.ji.sjtu.edu.cn:2222/JOJ/JOJ3-examples.git
-	branch = healthcheck/whitelistedchars-invalid
 [submodule "examples/healthcheck/whitelistedchars-success"]
 	path = examples/healthcheck/whitelistedchars-success
 	url = ssh://git@focs.ji.sjtu.edu.cn:2222/JOJ/JOJ3-examples.git
diff --git a/examples/healthcheck/whitelistedchars-invalid b/examples/healthcheck/whitelistedchars-invalid
deleted file mode 160000
index 5c56a61..0000000
--- a/examples/healthcheck/whitelistedchars-invalid
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 5c56a615bd2462829a97b8326b31c64aec08df78