In a wireless communication system, a user equipment (UE) may reselect a sidelink resource to be used for vehicle-to-everything (V2X) communication. The reselection of sidelink resource may be triggered by various conditions. In particular, the reselection of the sidelink resources may be triggered when a value of sidelink resource reselection counter is zero. More specifically, the UE determines that data for the V2X communication is available in a sidelink traffic channel (STCH), determines that a value of the sidelink resource reselection counter is zero, and reselects the sidelink resources.