1. A method for transmitting, by a user equipment (UE), urgent data in a wireless communication system, the method comprising:transmitting, to a base station, a fast UL grant request requesting a uplink resource allocation for transmitting a urgent data;
receiving, from the base station, a fast UL grant corresponding to the fast UL grant request; and
transmitting, to the base station, the urgent data based on the fast UL grant;
wherein the fast UL grant request is included in a medium access control information element (MAC CE) or is a specific preamble index transmitted on a physical random access channel (PRACH).