diff --git a/web/service/inbound.go b/web/service/inbound.go
index cb4f402b..e0c80d69 100644
--- a/web/service/inbound.go
+++ b/web/service/inbound.go
@@ -849,6 +849,9 @@ func (s *InboundService) AddInboundClient(data *model.Inbound) (bool, error) {
 
 	// Secure client ID
 	for _, client := range clients {
+		if strings.TrimSpace(client.Email) == "" {
+			return false, common.NewError("client email is required")
+		}
 		switch oldInbound.Protocol {
 		case "trojan":
 			if client.Password == "" {
@@ -1317,8 +1320,11 @@ func (s *InboundService) UpdateInboundClient(data *model.Inbound, clientId strin
 	if newClientId == "" || clientIndex == -1 {
 		return false, common.NewError("empty client ID")
 	}
+	if strings.TrimSpace(clients[0].Email) == "" {
+		return false, common.NewError("client email is required")
+	}
 
-	if len(clients[0].Email) > 0 && clients[0].Email != oldEmail {
+	if clients[0].Email != oldEmail {
 		existEmail, err := s.checkEmailsExistForClients(clients)
 		if err != nil {
 			return false, err