diff --git a/services/param/adapter/param_dac.c b/services/param/adapter/param_dac.c
index adaca666f..ea824a3ff 100644
--- a/services/param/adapter/param_dac.c
+++ b/services/param/adapter/param_dac.c
@@ -25,6 +25,7 @@
 #include "param_utils.h"
 #include "param_base.h"
 
+#define MAX_MEMBER_IN_GROUP  128
 #define MAX_BUF_SIZE  1024
 #define INVALID_MODE 0550
 #ifdef STARTUP_INIT_TEST
@@ -124,30 +125,76 @@ static int FreeLocalSecurityLabel(ParamSecurityLabel *srcLabel)
     return 0;
 }
 
+static int DacGetGroupMember(gid_t gid, uid_t *member, uint32_t *memberSize)
+{
+    uint32_t inputLen = *memberSize;
+    *memberSize = 0;
+    struct group *data = getgrgid(gid);
+    if (data == NULL || data->gr_mem == NULL) {
+        return 0;
+    }
+    int i = 0;
+    int memIndex = 0;
+    while (data->gr_mem[i]) {
+        uid_t uid;
+        GetUserIdByName(&uid, data->gr_mem[i]);
+        if (INVALID_UID(uid)) {
+            i++;
+            continue;
+        }
+        if ((memIndex + 1) > inputLen) {
+            PARAM_LOGE("Not enough memory for uid member %u", gid);
+            break;
+        }
+        member[memIndex++] = uid;
+        i++;
+    }
+    uid_t uid = 0;
+    GetUserIdByName(&uid, data->gr_name);
+    if (!INVALID_UID(uid) && ((memIndex + 1) < inputLen)) {
+        member[memIndex++] = uid;
+    }
+    *memberSize = memIndex;
+    return 0;
+}
+
 static int LoadOneParam_(const uint32_t *context, const char *name, const char *value)
 {
-    ParamAuditData auditData = {0};
-    auditData.dacData.gid = -1;
-    auditData.dacData.uid = -1;
-    auditData.name = name;
-    int ret = GetParamDacData(&auditData.dacData, value);
+    ParamAuditData *auditData = (ParamAuditData *)context;
+    auditData->dacData.gid = -1;
+    auditData->dacData.uid = -1;
+    auditData->name = name;
+    int ret = GetParamDacData(&auditData->dacData, value);
     PARAM_CHECK(ret == 0, return -1, "Failed to get param info %d %s", ret, name);
-    if (INVALID_UID(auditData.dacData.gid) || INVALID_UID(auditData.dacData.uid)) {
-        PARAM_LOGW("Invalid dac for '%s' gid %d uid %d", name, auditData.dacData.gid, auditData.dacData.uid);
+    if (INVALID_UID(auditData->dacData.gid) || INVALID_UID(auditData->dacData.uid)) {
+        PARAM_LOGW("Invalid dac for '%s' gid %d uid %d", name, auditData->dacData.gid, auditData->dacData.uid);
     }
-    AddSecurityLabel(&auditData);
+    // get uid from group
+    auditData->memberNum = MAX_MEMBER_IN_GROUP;
+    ret = DacGetGroupMember(auditData->dacData.gid, auditData->members, &auditData->memberNum);
+    if (ret != 0) {
+        auditData->memberNum = 1;
+        auditData->members[0] = auditData->dacData.gid;
+    }
+    AddSecurityLabel(auditData);
     return 0;
 }
 
 static int LoadParamLabels(const char *fileName)
 {
+    ParamAuditData *auditData = (ParamAuditData *)calloc(1,
+        sizeof(ParamAuditData) + sizeof(uid_t) * MAX_MEMBER_IN_GROUP);
+    if (auditData == NULL) {
+        PARAM_LOGE("Failed to alloc memory %s", fileName);
+        return 0;
+    }
     uint32_t infoCount = 0;
     FILE *fp = fopen(fileName, "r");
     const uint32_t buffSize = PARAM_NAME_LEN_MAX + PARAM_CONST_VALUE_LEN_MAX + 10;  // 10 size
     char *buff = (char *)calloc(1, buffSize);
     while (fp != NULL && buff != NULL && fgets(buff, buffSize, fp) != NULL) {
         buff[buffSize - 1] = '\0';
-        int ret = SplitParamString(buff, NULL, 0, LoadOneParam_, NULL);
+        int ret = SplitParamString(buff, NULL, 0, LoadOneParam_, (const uint32_t *)auditData);
         if (ret != 0) {
             PARAM_LOGE("Failed to split string %s fileName %s", buff, fileName);
             continue;
@@ -161,6 +208,9 @@ static int LoadParamLabels(const char *fileName)
     if (buff != NULL) {
         free(buff);
     }
+    if (auditData != NULL) {
+        free(auditData);
+    }
     return 0;
 }
 
@@ -237,127 +287,3 @@ INIT_LOCAL_API int RegisterSecurityDacOps(ParamSecurityOps *ops, int isInit)
     }
     return ret;
 }
-
-static void AddGroupUser(const char *userName, gid_t gid)
-{
-    if (userName == NULL || strlen(userName) == 0) {
-        return;
-    }
-    uid_t uid = 0;
-    GetUserIdByName(&uid, userName);
-    PARAM_LOGV("Add group user '%s' gid %d uid %d", userName, gid, uid);
-    if (INVALID_UID(gid) || INVALID_UID(uid)) {
-        PARAM_LOGW("Invalid user for '%s' gid %d uid %d", userName, gid, uid);
-        return;
-    }
-    char buffer[USER_BUFFER_LEN] = {0};
-    int ret = PARAM_SPRINTF(buffer, sizeof(buffer), GROUP_FORMAT, gid, uid);
-    PARAM_CHECK(ret >= 0, return, "Failed to format name for %d.%d", gid, uid);
-    (void)AddParamEntry(WORKSPACE_INDEX_BASE, PARAM_TYPE_STRING, buffer, "1");
-}
-
-#ifdef PARAM_DECODE_GROUPID_FROM_FILE
-static char *UserNameTrim(char *str)
-{
-    if (str == NULL) {
-        return NULL;
-    }
-    size_t len = strlen(str);
-    if (str == NULL || len == 0) {
-        return NULL;
-    }
-    char *end = str + len - 1;
-    while (end >= str && (*end == ' ' || *end == '\t' || *end == '\n' || *end == '\r')) {
-        *end = '\0';
-        end--;
-    }
-    len = strlen(str);
-    char *head = str;
-    end = str + strlen(str);
-    while (head < end && (*head == ' ' || *head == '\t' || *head == '\n' || *head == '\r')) {
-        *head = '\0';
-        head++;
-    }
-    if (strlen(str) == 0) {
-        return NULL;
-    }
-    return head;
-}
-
-static void LoadGroupUser_(void)
-{
-    // decode group file
-    FILE *fp = fopen(GROUP_FILE_PATH, "r");
-    const uint32_t buffSize = 1024;  // 1024 max buffer for decode
-    char *buff = (char *)calloc(1, buffSize);
-    while (fp != NULL && buff != NULL && fgets(buff, buffSize, fp) != NULL) {
-        buff[buffSize - 1] = '\0';
-        // deviceprivate:x:1053:root,shell,system,samgr,hdf_devmgr,deviceinfo,dsoftbus,dms,account
-        char *buffer = UserNameTrim(buff);
-        PARAM_CHECK(buffer != NULL, continue, "Invalid buffer %s", buff);
-
-        PARAM_LOGV("LoadGroupUser_ '%s'", buffer);
-        // group name
-        char *groupName = strtok(buffer, ":");
-        groupName = UserNameTrim(groupName);
-        PARAM_CHECK(groupName != NULL, continue, "Invalid group name %s", buff);
-        gid_t gid = -1;
-        GetGroupIdByName(&gid, groupName);
-
-        // skip x
-        (void)strtok(NULL, ":");
-        char *strGid = strtok(NULL, ":");
-        char *userName = strGid + strlen(strGid) + 1;
-        userName = UserNameTrim(userName);
-        PARAM_LOGV("LoadGroupUser_ %s userName '%s'", groupName, userName);
-        if (userName == NULL) {
-            AddGroupUser(groupName, gid);
-            continue;
-        }
-        char *tmp = strtok(userName, ",");
-        while (tmp != NULL) {
-            PARAM_LOGV("LoadGroupUser_ %s userName '%s'", groupName, tmp);
-            AddGroupUser(UserNameTrim(tmp), gid);
-            userName = tmp + strlen(tmp) + 1;
-            tmp = strtok(NULL, ",");
-        }
-        // last username
-        if (userName != NULL) {
-            AddGroupUser(UserNameTrim(userName), gid);
-        }
-    }
-    if (fp != NULL) {
-        (void)fclose(fp);
-    }
-    if (buff != NULL) {
-        free(buff);
-    }
-    return;
-}
-#else
-static void LoadGroupUser_(void)
-{
-    struct group *data = NULL;
-    while ((data = getgrent()) != NULL) {
-        if (data->gr_name == NULL || data->gr_mem == NULL) {
-            continue;
-        }
-        if (data->gr_mem[0] == NULL) { // default user in group
-            AddGroupUser(data->gr_name, data->gr_gid);
-            continue;
-        }
-        int index = 0;
-        while (data->gr_mem[index]) { // user in this group
-            AddGroupUser(data->gr_mem[index], data->gr_gid);
-            index++;
-        }
-    }
-    endgrent();
-}
-#endif
-
-INIT_LOCAL_API void LoadGroupUser(void)
-{
-    PARAM_LOGV("LoadGroupUser ");
-    LoadGroupUser_();
-}
diff --git a/services/param/adapter/param_selinux.c b/services/param/adapter/param_selinux.c
index 597490794..5820d5248 100644
--- a/services/param/adapter/param_selinux.c
+++ b/services/param/adapter/param_selinux.c
@@ -234,6 +234,8 @@ static void HandleSelinuxLabelForPermission(const ParameterNode *paramNode, int
     auditData.dacData.paramType = node->type;
     auditData.selinuxIndex = labelIndex;
     auditData.name = paramNode->paraName;
+    auditData.memberNum = 1;
+    auditData.members[0] = node->gid;
     AddSecurityLabel(&auditData);
 }
 
diff --git a/services/param/base/param_base.c b/services/param/base/param_base.c
index 6348a3920..7b064d3c2 100644
--- a/services/param/base/param_base.c
+++ b/services/param/base/param_base.c
@@ -124,9 +124,8 @@ static int CheckNeedInit(int onlyRead, const PARAM_WORKSPACE_OPS *ops)
 
 INIT_INNER_API int InitParamWorkSpace(int onlyRead, const PARAM_WORKSPACE_OPS *ops)
 {
-    if (CheckNeedInit(onlyRead, ops) == 0) {
-        return 0;
-    }
+    PARAM_ONLY_CHECK(CheckNeedInit(onlyRead, ops) != 0, return 0);
+
     paramMutexEnvInit();
     g_paramWorkSpace.maxLabelIndex = PARAM_DEF_SELINUX_LABEL;
     if (!PARAM_TEST_FLAG(g_paramWorkSpace.flags, WORKSPACE_FLAGS_INIT)) {
@@ -151,8 +150,6 @@ INIT_INNER_API int InitParamWorkSpace(int onlyRead, const PARAM_WORKSPACE_OPS *o
     PARAM_CHECK(ret == 0, return -1, "Failed to add dac workspace");
 #endif
     if (onlyRead == 0) {
-        // load user info for dac
-        LoadGroupUser();
         // add default dac policy
         ParamAuditData auditData = {0};
         auditData.name = "#";
@@ -160,6 +157,8 @@ INIT_INNER_API int InitParamWorkSpace(int onlyRead, const PARAM_WORKSPACE_OPS *o
         auditData.dacData.uid = DAC_DEFAULT_USER;
         auditData.dacData.mode = DAC_DEFAULT_MODE; // 0774 default mode
         auditData.dacData.paramType = PARAM_TYPE_STRING;
+        auditData.memberNum = 1;
+        auditData.members[0] = DAC_DEFAULT_GROUP;
 #ifdef PARAM_SUPPORT_SELINUX
         auditData.selinuxIndex = INVALID_SELINUX_INDEX;
 #endif
@@ -364,14 +363,12 @@ STATIC_INLINE int ReadParamWithCheck(WorkSpace **workspace, const char *name, ui
     return ret;
 }
 
-static int CheckUserInGroup(WorkSpace *space, gid_t groupId, uid_t uid)
+static int CheckUserInGroup(WorkSpace *space, const ParamSecurityNode *node, uid_t uid)
 {
-    char buffer[USER_BUFFER_LEN] = {0};
-    int ret = PARAM_SPRINTF(buffer, sizeof(buffer), GROUP_FORMAT, groupId, uid);
-    PARAM_CHECK(ret >= 0, return -1, "Failed to format name for "GROUP_FORMAT, groupId, uid);
-    ParamNode *node = GetParamNode(WORKSPACE_INDEX_BASE, buffer);
-    if (node != NULL) {
-        return 0;
+    for (uint32_t i = 0; i < node->memberNum; i++) {
+        if (node->members[i] == uid) {
+            return 0;
+        }
     }
     return -1;
 }
@@ -436,7 +433,7 @@ STATIC_INLINE int DacCheckParamPermission(const ParamLabelIndex *labelIndex,
         return DAC_RESULT_PERMISSION;
     }
     // 4, check user in group
-    if (CheckUserInGroup(space, node->gid, srcLabel->cred.uid) == 0) {
+    if (CheckUserInGroup(space, node, srcLabel->cred.uid) == 0) {
         localMode = (mode & (DAC_READ | DAC_WRITE | DAC_WATCH)) >> DAC_GROUP_START;
         if ((node->mode & localMode) != 0) {
             return DAC_RESULT_PERMISSION;
diff --git a/services/param/base/param_trie.c b/services/param/base/param_trie.c
index b270b7696..a3ba0d307 100644
--- a/services/param/base/param_trie.c
+++ b/services/param/base/param_trie.c
@@ -237,7 +237,7 @@ INIT_LOCAL_API uint32_t AddParamSecurityNode(WorkSpace *workSpace, const ParamAu
 {
     PARAM_CHECK(CheckWorkSpace(workSpace) == 0, return 0, "Invalid workSpace");
     PARAM_CHECK(auditData != NULL, return 0, "Invalid auditData");
-    uint32_t realLen = sizeof(ParamSecurityNode);
+    uint32_t realLen = sizeof(ParamSecurityNode) + sizeof(uid_t) * auditData->memberNum;
     PARAM_CHECK((workSpace->area->currOffset + realLen) < workSpace->area->dataSize, return 0,
         "Failed to allocate currOffset %u, dataSize %u datalen %u",
         workSpace->area->currOffset, workSpace->area->dataSize, realLen);
@@ -251,6 +251,13 @@ INIT_LOCAL_API uint32_t AddParamSecurityNode(WorkSpace *workSpace, const ParamAu
 #else
     node->selinuxIndex = 0;
 #endif
+    if (auditData->memberNum > 0) {
+        // copy member
+        int ret = PARAM_MEMCPY(node->members,
+            realLen - sizeof(ParamSecurityNode), auditData->members, auditData->memberNum * sizeof(uid_t));
+        PARAM_CHECK(ret == 0, return 0, "Failed to copy members");
+    }
+    node->memberNum = auditData->memberNum;
     uint32_t offset = workSpace->area->currOffset;
     workSpace->area->currOffset += realLen;
     workSpace->area->securityNodeCount++;
diff --git a/services/param/include/param_common.h b/services/param/include/param_common.h
index 32386923c..fc4b2cef1 100644
--- a/services/param/include/param_common.h
+++ b/services/param/include/param_common.h
@@ -87,6 +87,8 @@ typedef struct {
     uint16_t mode;
     uint8_t type;
     uint8_t length;
+    uint32_t memberNum;
+    uid_t members[0];
 } ParamSecurityNode;
 
 typedef struct {
diff --git a/services/param/include/param_security.h b/services/param/include/param_security.h
index c82b95c70..17fcd72ce 100644
--- a/services/param/include/param_security.h
+++ b/services/param/include/param_security.h
@@ -88,6 +88,8 @@ typedef struct {
     char label[SELINUX_CONTENT_LEN];
     uint32_t selinuxIndex;
 #endif
+    uint32_t memberNum;
+    uid_t members[1];
 } ParamAuditData;
 
 struct WorkSpace_;
@@ -127,7 +129,6 @@ INIT_LOCAL_API int RegisterSecuritySelinuxOps(ParamSecurityOps *ops, int isInit)
 #endif
 
 INIT_LOCAL_API ParamSecurityOps *GetParamSecurityOps(int type);
-INIT_LOCAL_API void LoadGroupUser(void);
 INIT_LOCAL_API int RegisterSecurityDacOps(ParamSecurityOps *ops, int isInit);
 INIT_LOCAL_API int RegisterSecurityOps(int onlyRead);
 
diff --git a/services/param/liteos/param_litedac.c b/services/param/liteos/param_litedac.c
index 1c2cafe1e..ef9de763f 100644
--- a/services/param/liteos/param_litedac.c
+++ b/services/param/liteos/param_litedac.c
@@ -81,7 +81,3 @@ INIT_LOCAL_API int RegisterSecurityDacOps(ParamSecurityOps *ops, int isInit)
     }
     return ret;
 }
-
-INIT_LOCAL_API void LoadGroupUser(void)
-{
-}
diff --git a/services/param/manager/param_manager.c b/services/param/manager/param_manager.c
index 0774a5996..96419f724 100644
--- a/services/param/manager/param_manager.c
+++ b/services/param/manager/param_manager.c
@@ -141,12 +141,20 @@ static int DumpTrieDataNodeTraversal(const WorkSpace *workSpace, const ParamTrie
                 entry->commitId, entry->keyLength, entry->valueLength, entry->data);
         }
     }
-    if (current->labelIndex != 0 && verbose) {
-        ParamSecurityNode *label = (ParamSecurityNode *)GetTrieNode(workSpace, current->labelIndex);
-        if (label != NULL) {
-            PARAM_DUMP("\tparameter label dac %u %u %o selinuxIndex %u \n",
-                label->uid, label->gid, label->mode, label->selinuxIndex);
-        }
+    if (current->labelIndex == 0) {
+        return 0;
+    }
+    ParamSecurityNode *label = (ParamSecurityNode *)GetTrieNode(workSpace, current->labelIndex);
+    if (label == NULL) {
+        return 0;
+    }
+    PARAM_DUMP("\tparameter label dac %u %u 0%o \n", label->uid, label->gid, label->mode);
+    PARAM_DUMP("\tparameter label dac member [%u] ", label->memberNum);
+    for (uint32_t i = 0; i < label->memberNum; i++) {
+        PARAM_DUMP(" %u", label->members[i]);
+    }
+    if (label->memberNum > 0) {
+        PARAM_DUMP("\n");
     }
     return 0;
 }