A broadcast/multicast service information receiving method and broadcast/multicast service information transmitting method using the same are disclosed. The present invention includes the steps of receiving length information of a BCMCS component flow discriminator (BCMCS Flow Discriminator) configuring a BCMC service flow identifier (BCMCS Flow Identifier) and receiving information for a number of BCMCS component flow discriminators configuring the BCMC service flow identifier using a bit number corresponding to a value of the length information of the BCMCS component flow discriminator. Accordingly, the information for the BCMCS component flow identifier can be efficiently transmitted and received.