Embodiments provide a method for selecting a network by a terminal and a dual-standby terminal. The method includes: enabling, by a first network processing module, a circuit switched (CS) domain to preferably camp on a first network, and executing a CS domain service; enabling, by a second network processing module, a packet switched (PS) domain to preferably camp on a second network, and executing a PS domain service; wherein, signal quality of the first network is better than that of the second network, and a data transmission rate of the second network is higher than that of the first network; and closing the second network processing module when no PS domain service exists in a set duration. These embodiments help improve the service quality and reduce power consumption of the terminal.