A method and an apparatus for transmitting SI(Scheduling Information) in a mobile communication system are provided to allow a base station to obtain information required for scheduling by transferring SI of a terminal to a cell belonging to a serving RLS(Radio Link Set) when several RLSs are formed at the terminal in a soft handover area. When SI is generated, the SI is configured as a MAC(Media Access Control)-e PDU(Protocol Data Unit) and transmitted to cells of a serving RLS(410) and cells of a non-serving RLS(415). When NACK with respect to the MAC-e PDU arrives from the cells of the serving RLS, the MAC-e PDU is re-transmitted. When the number of re-transmissions of the SI data reaches a maximum re-transmission limit, it is determined that the transmission of the SI has failed, and the SI is inserted into a new MAC-e PDU and then transmitted.