The present disclosure relates to a 5th generation communication system provided to support higher data rates beyond a 4th generation communication system such as Long Term Evolution. The invention provides a method for acquiring system information SI by a user equipment in a wireless communication system. The method includes receiving system information including first information and second information from a base station, where the first information is associated with one or more preambles, and the second information is associated with a physical random access channel PRACH resource; basedon the first information associated with one or more preambles and the reference signal received power RSRP associated with at least one signal, selecting the preambles; based on the second information associated with the PRACH resource, a preamble code for the SI request is sent to the base station; and receiving a response message associated with the preamble from the base station, wherein the response message includes other system information.