Abstract: For underwater multi-target bearing tracking and Measurement-to-Track Association(MTA) problems,a unified method for detection and tracking based on particle filter is proposed.This method doesn't require bearing observation values in the filtering process.The likelihood function of particles is directly estimated according to beamforming energy.The particles with small weight are evolved after crossover and mutation operators.The diversity of offspring particles is improved by low discrepancy sequence resampling.It could effectively realize correct multi-target tracking and avoid MTA challenges.The simulation result shows that the method can continuously and accurately track target bearings in the case of temporary target disappearance and multi-target intersection.The effectiveness of the method is verified by using the Unmanned Underwater Vehicle(UUV) experimental data and the vertical direction tracking error is within 3°.The estimated result is close to the real value even when the motion model is mismatched.