A method and apparatus for selecting a sidelink resource for a sidelink CSI reporting in a wireless communication system is provided. A first wireless device triggers the SL CSI reporting for the PC5-RRC connection. A first wireless device determines to create a sidelink grant corresponding to transmission of a single MAC PDU based on the triggered SL CSI reporting or a SL data available for transmission. A first wireless device triggers a resource selection procedure based on the determination. A first wireless device selects a sidelink resource in the resource selection procedure.