The present invention provides a method for realizing transmission of multiprotocol client signals in a distributed base station subsystem, comprising: encapsulating client signals by a GFP-T frame; and mapping the GFP-T frame into a lower-layer transmission link to realize the transmission of client signals. The lower-layer transmission link is a common public radio interface CPRI link. The client signals are one of the following: baseband I/Q signals of WCDMA supported by CPRI protocol, baseband I/Q signals of radio interface protocols other than WCDMA, structured signals of E1/T1, STM-1 and other constant-rate links, structured variable-rate link signals such as Ethernet MAC frame signals, PPP/HDLC frame signals, etc. This method is also applicable to other types of synchronous transmission links between a remote radio unit and a primary baseband processing unit, e.g., the links as specified by OBSAI (Open Base Station Architecture Initiative).