diff --git a/charts/tidb-backup/templates/scripts/_start_backup.sh.tpl b/charts/tidb-backup/templates/scripts/_start_backup.sh.tpl
index 8c6c8e8843..38f7b5bf35 100644
--- a/charts/tidb-backup/templates/scripts/_start_backup.sh.tpl
+++ b/charts/tidb-backup/templates/scripts/_start_backup.sh.tpl
@@ -6,12 +6,18 @@ dirname=/data/${BACKUP_NAME}
 echo "making dir ${dirname}"
 mkdir -p ${dirname}
 
-gc_life_time=`/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "select variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"`
+password_str=""
+if [ -n "${TIDB_PASSWORD}" ];
+then
+    password_str="-p${TIDB_PASSWORD}"
+fi
+
+gc_life_time=`/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "select variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"`
 echo "Old TiKV GC life time is ${gc_life_time}"
 
 echo "Increase TiKV GC life time to 3h"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "update mysql.tidb set variable_value='3h' where variable_name='tikv_gc_life_time';"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "update mysql.tidb set variable_value='3h' where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
 
 if [ -n "{{ .Values.initialCommitTs }}" ];
 then
@@ -31,8 +37,8 @@ fi
   {{ .Values.backupOptions }} ${snapshot_args:-}
 
 echo "Reset TiKV GC life time to ${gc_life_time}"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "update mysql.tidb set variable_value='${gc_life_time}' where variable_name='tikv_gc_life_time';"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "update mysql.tidb set variable_value='${gc_life_time}' where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
 
 {{- if .Values.gcp }}
 uploader \
diff --git a/charts/tidb-backup/templates/scripts/_start_restore.sh.tpl b/charts/tidb-backup/templates/scripts/_start_restore.sh.tpl
index e32c57d105..1489630a81 100644
--- a/charts/tidb-backup/templates/scripts/_start_restore.sh.tpl
+++ b/charts/tidb-backup/templates/scripts/_start_restore.sh.tpl
@@ -30,8 +30,14 @@ downloader \
   --destDir=/data
 {{- end }}
 
+password_str=""
+if [ -n "${TIDB_PASSWORD}" ];
+then
+    password_str="-p${TIDB_PASSWORD}"
+fi
+
 count=1
-while ! mysql -u ${TIDB_USER} -h `eval echo '${'$host'}'` -P 4000 -p${TIDB_PASSWORD} -e 'select version();'
+while ! mysql -u ${TIDB_USER} -h `eval echo '${'$host'}'` -P 4000 ${password_str} -e 'select version();'
 do
   echo "waiting for tidb, retry ${count} times ..."
   sleep 10
diff --git a/charts/tidb-cluster/templates/scripts/_start_scheduled_backup.sh.tpl b/charts/tidb-cluster/templates/scripts/_start_scheduled_backup.sh.tpl
index 632237adff..bca4afb048 100755
--- a/charts/tidb-cluster/templates/scripts/_start_scheduled_backup.sh.tpl
+++ b/charts/tidb-cluster/templates/scripts/_start_scheduled_backup.sh.tpl
@@ -10,12 +10,18 @@ backupPath=/data/${backupName}
 echo "making dir ${backupPath}"
 mkdir -p ${backupPath}
 
-gc_life_time=`/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "select variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"`
+password_str=""
+if [ -n "${TIDB_PASSWORD}" ];
+then
+    password_str="-p${TIDB_PASSWORD}"
+fi
+
+gc_life_time=`/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "select variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"`
 echo "Old TiKV GC life time is ${gc_life_time}"
 
 echo "Increase TiKV GC life time to 3h"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "update mysql.tidb set variable_value='3h' where variable_name='tikv_gc_life_time';"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "update mysql.tidb set variable_value='3h' where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
 
 /mydumper \
   --outputdir=${backupPath} \
@@ -29,8 +35,8 @@ echo "Increase TiKV GC life time to 3h"
   {{ .Values.scheduledBackup.options }}
 
 echo "Reset TiKV GC life time to ${gc_life_time}"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "update mysql.tidb set variable_value='${gc_life_time}' where variable_name='tikv_gc_life_time';"
-/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} -p${TIDB_PASSWORD} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "update mysql.tidb set variable_value='${gc_life_time}' where variable_name='tikv_gc_life_time';"
+/usr/bin/mysql -h${host} -P4000 -u${TIDB_USER} ${password_str} -Nse "select variable_name,variable_value from mysql.tidb where variable_name='tikv_gc_life_time';"
 
 {{- if .Values.scheduledBackup.gcp }}
 uploader \
diff --git a/tests/actions.go b/tests/actions.go
index 846ca8dce8..bc8bc06820 100644
--- a/tests/actions.go
+++ b/tests/actions.go
@@ -565,6 +565,11 @@ func (oa *operatorActions) CleanTidbCluster(info *TidbClusterConfig) error {
 		return fmt.Errorf("failed to delete dir pod %v", err)
 	}
 
+	err = oa.kubeCli.CoreV1().Secrets(info.Namespace).Delete(info.InitSecretName, &metav1.DeleteOptions{})
+	if err != nil && !errors.IsNotFound(err) {
+		return fmt.Errorf("failed to delete secret: %s, %v", info.InitSecretName, err)
+	}
+
 	setStr := label.New().Instance(info.ClusterName).String()
 
 	resources := []string{"pvc"}
@@ -1722,9 +1727,13 @@ func (oa *operatorActions) DeployAdHocBackup(info *TidbClusterConfig) error {
 	oa.EmitEvent(info, "DeployAdHocBackup")
 	glog.Infof("begin to deploy adhoc backup cluster[%s] namespace[%s]", info.ClusterName, info.Namespace)
 
-	getTSCmd := fmt.Sprintf("set -euo pipefail; mysql -u%s -p%s -h%s-tidb.%s -P 4000 -Nse 'show master status;' | awk '{print $2}'",
+	passwdStr := ""
+	if info.Password != "" {
+		passwdStr = fmt.Sprintf("-p%s", info.Password)
+	}
+	getTSCmd := fmt.Sprintf("set -euo pipefail; mysql -u%s %s -h%s-tidb.%s -P 4000 -Nse 'show master status;' | awk '{print $2}'",
 		info.UserName,
-		info.Password,
+		passwdStr,
 		info.ClusterName,
 		info.Namespace,
 	)
diff --git a/tests/cmd/e2e/main.go b/tests/cmd/e2e/main.go
index 97b3ac3eaa..331bdf8904 100644
--- a/tests/cmd/e2e/main.go
+++ b/tests/cmd/e2e/main.go
@@ -84,7 +84,7 @@ func main() {
 			TiKVImage:        fmt.Sprintf("pingcap/tikv:%s", initTidbVersion),
 			TiDBImage:        fmt.Sprintf("pingcap/tidb:%s", initTidbVersion),
 			StorageClassName: "local-storage",
-			Password:         "admin",
+			Password:         "",
 			UserName:         "root",
 			InitSecretName:   fmt.Sprintf("%s-set-secret", name1),
 			BackupSecretName: fmt.Sprintf("%s-backup-secret", name1),