diff --git a/constant/metadata.go b/constant/metadata.go
index fe1b7c50..4ddb1bd9 100644
--- a/constant/metadata.go
+++ b/constant/metadata.go
@@ -83,7 +83,7 @@ type Metadata struct {
 	AddrType    int        `json:"-"`
 	Host        string     `json:"host"`
 	DNSMode     DNSMode    `json:"dnsMode"`
-	Uid         int32      `json:"uid"`
+	Uid         *int32     `json:"uid"`
 	Process     string     `json:"process"`
 	ProcessPath string     `json:"processPath"`
 }
@@ -101,10 +101,10 @@ func (m *Metadata) SourceDetail() string {
 		return fmt.Sprintf("[%s]", ClashName)
 	}
 
-	if m.Process != "" && m.Uid != 0 {
-		return fmt.Sprintf("%s(%s, uid=%d)", m.SourceAddress(), m.Process, m.Uid)
-	} else if m.Uid != 0 {
-		return fmt.Sprintf("%s(%d)", m.SourceAddress(), m.Uid)
+	if m.Process != "" && m.Uid != nil {
+		return fmt.Sprintf("%s(%s, uid=%d)", m.SourceAddress(), m.Process, *m.Uid)
+	} else if m.Uid != nil {
+		return fmt.Sprintf("%s(%d)", m.SourceAddress(), *m.Uid)
 	} else if m.Process != "" {
 		return fmt.Sprintf("%s(%s)", m.SourceAddress(), m.Process)
 	} else {
diff --git a/rule/common/uid.go b/rule/common/uid.go
index 2ab1beb6..00f0c3d8 100644
--- a/rule/common/uid.go
+++ b/rule/common/uid.go
@@ -72,10 +72,10 @@ func (u *Uid) Match(metadata *C.Metadata) bool {
 		return false
 	}
 	var uid int32
-	if metadata.Uid != 0 {
-		uid = metadata.Uid
+	if metadata.Uid != nil {
+		uid = *metadata.Uid
 	} else if uid, err = process.FindUid(metadata.NetWork.String(), metadata.SrcIP, srcPort); err == nil {
-		metadata.Uid = uid
+		metadata.Uid = &uid
 	} else {
 		log.Warnln("[UID] could not get uid from %s", metadata.String())
 		return false