An apparatus and method for transmitting data in communication

A method and an apparatus for transmitting data in a communication system are provided to omit service flow classification work and efficiently use radio resources by mapping ROHC channels with service flows in a one-to-one ratio. An apparatus for setting up ROHC(Robust Header Compression) channels in a communication system comprises an ROHC context ID creation part(214), an ROHC control part(212), and a service flow searching part(220). The ROHC context ID creation part maps ROHC channels to service flows, based on the transmission characteristics of packet data, in a one-to-one ratio. The ROHC context ID creation part creates IDs to classify the service flows mapped to the ROHC channels. The ROHC control part creates ROHC channels, and transmits ROHC parameter information, which includes information about service flows to be mapped to the ROHC channels in a one-to-one ratio, to the service flow searching part. The service flow searching part receives the ROHC parameter information, creates a new service flow, and transmits the information of the created service flow to the ROHC control part.