A power-saving apparatus for universal serial bus (USB) modem equipment is disclosed in the present invention, which includes: a personal computer and USB Modem equipment. Accordingly, a power-saving method for USB Modem equipment is provided in the present invention, which includes: regularly detecting whether selective suspending is allowed, if not allowed, processing a received request from an application program, and if allowed, transmitting an instruction for entering the selective suspending state to the USB Modem equipment; after receiving the instruction for entering the selective suspending state, the USB Modem equipment entering the selective suspending state. Thus, the present invention can realize that the USB Modem equipment enters the power-saving state in the idle period and resumes the work state when receiving a service request.