diff --git a/src/logservice/palf/log_config_mgr.cpp b/src/logservice/palf/log_config_mgr.cpp
index 1f4919b11a..5a88450d2f 100644
--- a/src/logservice/palf/log_config_mgr.cpp
+++ b/src/logservice/palf/log_config_mgr.cpp
@@ -239,7 +239,7 @@ int LogConfigMgr::set_initial_member_list(const common::ObMemberList &member_lis
     PALF_LOG(WARN, "LogConfigMgr not init", KR(ret));
   } else if (!member_list.is_valid() ||
              !arb_member.is_valid() ||
-             (member_list.get_member_number() & 1) != 0 ||
+             (replica_num & 1) != 0 ||
              replica_num <= 0 ||
              replica_num > OB_MAX_MEMBER_NUMBER ||
              INVALID_PROPOSAL_ID == proposal_id ||
diff --git a/unittest/logservice/test_log_config_mgr.cpp b/unittest/logservice/test_log_config_mgr.cpp
index cb763db171..9c7c1f1584 100644
--- a/unittest/logservice/test_log_config_mgr.cpp
+++ b/unittest/logservice/test_log_config_mgr.cpp
@@ -128,21 +128,24 @@ TEST_F(TestLogConfigMgr, test_set_initial_member_list)
     LogConfigVersion config_version;
     init_test_log_config_env(addr1, default_config_info, cm);
     // arb_member is self
-    EXPECT_EQ(OB_NOT_SUPPORTED, cm.set_initial_member_list(init_member_list, ObMember(addr1, 0), 3, learner_list, 1, config_version));
+    EXPECT_EQ(OB_NOT_SUPPORTED, cm.set_initial_member_list(init_member_list, ObMember(addr1, 0), 2, learner_list, 1, config_version));
     // arb_member overlaps with member_list
-    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr2, 0), 3, learner_list, 1, config_version));
-
+    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr2, 0), 2, learner_list, 1, config_version));
+    // invalid replica_num
+    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr3, 0), 3, learner_list, 1, config_version));
     // arb_member overlaps with learners
     learner_list.add_learner(ObMember(addr4, 0));
-    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr4, 0), 3, learner_list, 1, config_version));
+    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr4, 0), 2, learner_list, 1, config_version));
+    // do not reach majority
+    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr5, 0), 4, learner_list, 1, config_version));
     // learners overlap with member_list
     init_member_list.add_server(addr4);
-    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr5, 0), 3, learner_list, 1, config_version));
+    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr5, 0), 4, learner_list, 1, config_version));
 
     init_member_list.add_server(addr3);
     learner_list.reset();
     // do not reach majority
-    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr5, 0), 3, learner_list, 1, config_version));
+    EXPECT_EQ(OB_INVALID_ARGUMENT, cm.set_initial_member_list(init_member_list, ObMember(addr5, 0), 2, learner_list, 1, config_version));
     EXPECT_EQ(OB_SUCCESS, cm.set_initial_member_list(init_member_list, ObMember(addr5, 0), 4, learner_list, 1, config_version));
   }
 }