diff --git a/mugen.sh b/mugen.sh
index 366ca90e262..e3256ac8aa8 100644
--- a/mugen.sh
+++ b/mugen.sh
@@ -328,7 +328,7 @@ function run_test_suite() {
 }
 
 function run_all_cases() {
-    mapfile -t test_suites < <(find "${OET_PATH}"/suite2cases/ -type f -name "*.json" | awk -F '/' '{print $NF}' | sed -e 's/.json$//g')
+    mapfile -t test_suites < <(find "${OET_PATH}"/suite2cases/ -type f -name "*.json" | awk -F '/' '{print $NF}' | sed -e 's/.json$//g' | sort -u)
     test ${#test_suites[@]} -eq 0 && {
         LOG_ERROR "Can't find recording about test_suites."
         return 1
@@ -339,7 +339,7 @@ function run_all_cases() {
         local this_copy=true
     fi
 
-    for test_suite in ${test_suites[*]}; do
+    for test_suite in "${test_suites[@]}"; do
         run_test_suite "$test_suite"
         COPY_DONE="no"
         local this_copy=true