A method and system for controlling signalling transmission in a power-saving mode are disclosed. The method includes that a terminal transmits a tracking area update request signalling or a routing area update request signalling to a new mobility management unit, wherein each signalling includes a power-saving parameter; and the new mobility management unit transmits a power-saving parameter to an old mobility management unit or a serving gateway. According to the disclosure, a network is enabled to keep pace with the power-saving mode of the terminal, and a paging message is transmitted only at activation time, thereby ensuring that the terminal may receive the paging message, and avoiding resource waste caused by repeated paging of the network.