Abstract: There are many micro-bubbles in the zone of ship wake, which makes it different from the normal sea water. A method to detect the signal of ship wake by two-path phase-locking amplification technology is proposed based on the ship wake optical characteristics. Lock-in amplifiers are good at weak signal detection and they are used widely in many areas. By using orthogonal lock-in amplifier technology to eliminate the laser drift of the laser detection system in the process of the ship wake detection, it can reduce the noise and make the detection system more sensitive and reliable.