Disclosed herein relates to a sleep mode operation method, and the method of updating a sleep mode operation according to the present invention may include receiving a service flow configuration request (DSx-REQ) message including a service flow parameter for service flow configuration and a sleep cycle ID (SCID) for changing a sleep mode according to the service flow configuration from a base station during a sleep mode listening window; transmitting a service flow configuration response (DSx-RSP) message including the SCID; configuring the service flow according to the service flow identifier; and changing an SCID to the SCID for updating the sleep mode operation.