Disclosed is a method for performing transmission frequency control for a subscriber line of a customer premise device by a transmission control apparatus in an access network structure in which at least one network management device and a plurality of customer premise devices are connected through a bundle cable including a plurality of subscriber lines. The transmission control method includes: setting a partial frequency band in an entire service frequency band provided by the subscriber line as a transmission frequency band of the customer premise device; and varying the transmission frequency band in the entire service frequency band when a triggering event occurs, in which traffic of the customer premise device is transmitted and received in the transmission frequency band.