Radio Frequency Identification is one of the most controversial technologies at present.It is very difficult to detect who reads a tag incorporated into products owned by a person,a significant concern to privacy threats in RFID system arises from this reason.User privacy problem is prior considersion for mobile RFID service,because most mobile RFID service based on end-user service.Propose a solution for user privacy protection,which is a modification of EPC Class 1 Generation 2 protocol,and introduce a privacy protection scenario for mobile RFID service using this method.