Method, device and system for discontinuous receiving

The invention discloses a method and a device for discontinuous receiving. The method comprises the following steps of: configuring at least two monitoring time lengths of discontinuous receiving; performing the discontinuous receiving according to a first monitoring time length of the at least two monitoring time lengths; when a set condition is satisfied, switching the first monitoring time length of discontinuous receiving into a second monitoring time length according to the configured at least two monitoring time lengths; and performing the discontinuous receiving according to the second monitoring time length. With the method and the device, additional RRC (radio resource control) signaling overhead can be avoided, and the complexity of the system is reduced.