A method and apparatus for logical channel prioritization (LCP) based on hybrid automatic repeat request (HARQ) feedback in a wireless communication system is provided. A wireless device selects a first logical channel with a highest priority among multiple logical channels having data available for transmission. When the first logical channel is configured with a hybrid automatic repeat request (HARQ) feedback, the wireless device selects one or more second logical channels configured with the HARQ feedback among the multiple logical channels. When the first logical channel is not configured with HARQ feedback, the wireless device selects one or more second logical channels not configured with the HARQ feedback among the multiple logical channels. The wireless device creates a data unit based on the first logical channel and the one or more second logical channels.