A cluster data processing method and system based on a unique identity control without requiring continuous network connection between the servers in the cluster and an external computer. The cluster sends a first data containing a controlling identity record to the external computer. The controlling identity record includes a unique identity and a control information. A load-balancing device of the cluster receives from the external computer a second data, which contains a controlling identity record corresponding to that of the first data. The cluster routes the second data according to the control information in the controlling identity record of the second data. The disclosed method and system may help avoid the overload problem of server resources and prevent low performance caused by continuous network connection that has to be maintained between the cluster and external server 190 in existing technology.