The embodiments of the present invention provide a paging processing method and system and also a serving gateway. The paging processing method includes: detecting, by a serving gateway, a fault of a mobility management element, determining a type of the fault, and reselecting a mobility management element according to the type of the fault; and sending, by the serving gateway, a downlink data notification message to the reselected mobility management element, whereupon the reselected mobility management element sends a paging message to a user equipment UE that is served by the faulty mobility management element before the fault occurs. With the method, system and serving gateway provided in the embodiments of the present invention, user experience is improved effectively.