The permanent magnet linear generator is widely applied in the direct-drive wave energy converter (DD-WEC) due to its high power density. A novel tubular permanent magnet linear generator is proposed to reduce the detent force. The proposed generator is designed to have a tubular structure with a permanent magnet ring and a coil winding. The detent force is reduced by optimizing the magnetic circuit and the coil winding configuration. The proposed generator is expected to improve the efficiency and reliability of the DD-WEC.