diff --git a/src/test/ha/standby_env.sh b/src/test/ha/standby_env.sh
index 253370391..b7bc0764d 100644
--- a/src/test/ha/standby_env.sh
+++ b/src/test/ha/standby_env.sh
@@ -104,11 +104,18 @@ function query_standby2()
 
 function query_standby3()
 {
- echo query standby2
+ echo query standby3
  gs_ctl query -D  $data_dir/datanode3_standby
 
 }
 
+function query_standby4()
+{
+ echo query standby4
+ gs_ctl query -D  $standby4_data_dir
+
+}
+
 function check_primary_startup()
 {
 echo checking primary startup
diff --git a/src/test/ha/testcase/cascade/clean_slot.sh b/src/test/ha/testcase/cascade/clean_slot.sh
index 1d089266e..793e4dbfc 100644
--- a/src/test/ha/testcase/cascade/clean_slot.sh
+++ b/src/test/ha/testcase/cascade/clean_slot.sh
@@ -1,52 +1,94 @@
+# This use case is used to test whether the primary can properly clean up the replication slots corresponding to the cascade standby.
+
 #!/bin/sh
- 
 source ./util.sh
- 
-function check_select_result()
+
+standby_mounted_cascade_datadir=""
+standby_mounted_cascade_port=""
+ports=($dn1_primary_port $standby1_port $standby2_port $standby3_port $standby4_port)
+datadirs=($primary_data_dir $standby1_data_dir $standby2_data_dir $standby3_data_dir $standby4_data_dir)
+
+function query_standby_mounted_cascade()
 {
-  if [ $(echo $result | grep "${1}" | wc -l) -eq 1 ]; then
-    echo "remote read successful"
+  standby_mounted_cascade_datadir=""
+  standby_mounted_cascade_port=""
+  for (( i=0; i<5; i++ )); do
+    local result=`gsql -tA -d $db -p ${ports[i]} -c "select count(*) from pg_get_replication_slots() where slot_name='dn_s4' and active='t';"`
+    if [[ X"${result}" = X"1" ]]; then
+      standby_mounted_cascade_datadir=${datadirs[i]}
+      standby_mounted_cascade_port=${ports[i]}
+      break
+    fi
+  done
+}
+
+function check_clean_cascade_slot_result()
+{
+  local port=$1
+  local result=`gsql -tA -d $db -p $port -c "select count(*) from pg_get_replication_slots() where slot_name='dn_s4' and active='f';"`
+  if [[ "${result}" = "0" ]]; then
+    echo "primary cleaned cascade slot successfully."
   else
-    echo "remote read failed $failed_keyword with [$result]"
+    echo "cascade slot still exists in primary! "
+    echo "clean cascade slot test failed $failed_keyword with [$result]."
+    echo "cascade slot info:"
+    gsql -d $db -p $port -c "select * from pg_get_replication_slots() where slot_name='dn_s4' and active='f';"
     exit 1
   fi
 }
- 
-function check_select_no_result()
-{
-  if [ $(echo $result | grep "${1}" | wc -l) -eq 0 ]; then
-    echo "remote read successful"
-  else
-    echo "remote read failed $failed_keyword with [$result]"
-    exit 1
-  fi
-}
- 
+
 function test_cascade_standby_clean_slot_func()
 {
   set_default
- 
+
+  # The initial state of the cluster is 1 primary and 4 standbies.
+
+  # start standby4 as cascade
   echo "base"
-  result=`gsql -d $db -p $dn1_primary_port -c "select * from pg_get_replication_slots();"`
-  check_select_result "dn_s2"
- 
-  kill_cascade_cluster
-  start_cascade_cluster
-  
- 
-  result=`gsql -d $db -p $dn1_primary_port -c "select * from pg_get_replication_slots();"`
-  check_select_no_result "dn_s2"
- 
-  switchover_to_cascade_standby
- 
-  result=`gsql -d $db -p $dn1_primary_port -c "select * from pg_get_replication_slots();"`
-  check_select_no_result "dn_s1"
- 
+  gs_ctl build -D $standby4_data_dir -M cascade_standby
+  sleep 1
+
+  query_primary
+  query_multi_standby
+
+  # case 1
+  check_clean_cascade_slot_result $dn1_primary_port
+  echo "case 1 passed"
+
+  # case 2    https://gitee.com/opengaussorg/dashboard?issue_id=I9JWCD
+  query_standby_mounted_cascade
+  gs_ctl switchover -D $standby_mounted_cascade_datadir
+  sleep 3
+  check_clean_cascade_slot_result $standby_mounted_cascade_port
+  sleep 1
+  gs_ctl switchover -D $primary_data_dir
+  sleep 3
+  check_clean_cascade_slot_result $dn1_primary_port
+  echo "case 2 passed"
+
+  # case 3    https://gitee.com/opengaussorg/dashboard?issue_id=I9VA9H&from=project-issue
+  query_primary
+  query_multi_standby
+  query_standby_mounted_cascade
+  gs_ctl stop -D $standby_mounted_cascade_datadir
+  sleep 1
+  query_standby4
+  gs_ctl start -D $standby_mounted_cascade_datadir -M standby
+  sleep 3
+  local result=`gsql -tA -d $db -p $standby_mounted_cascade_port -c "select count(*) from pg_get_replication_slots() where slot_name='dn_s4' and active='f';"`
+  if [[ "$result" != "1" ]]; then
+    echo "$failed_keyword with [$result]"
+    exit 1
+  fi
+  gs_ctl switchover -D $standby_mounted_cascade_datadir
+  sleep 3
+  check_clean_cascade_slot_result $standby_mounted_cascade_port
+  echo "case 3 passed"
 }
- 
+
 function tear_down() {
-  set_cascade_default
+  set_default
 }
- 
+
 test_cascade_standby_clean_slot_func
 tear_down
\ No newline at end of file