Regarding the problem that the Auxiliary Particle Filter Track-Before-Detect (APF-TBD) can not achieve good detection and tracking performance due to the lack of particles,an auxiliary particle filter track-before-detect based on optimized genetic re-sampling (OGRAPF-TBD) method is proposed.The optimized genetic re-sampling algorithm is applied in re-sampling of APF-TBD.In the re-sampling,high quality particles are chosen according to the weight,and new particles are obtained by crossover of sorting groups and mutation.The method not only maintains the advantage of APF-TBD in improving the accuracy of sampling particles by optimizing the importance distribution function,but also introduces the optimized genetic re-sampling idea into re-sampling,which can effectively solve the problem of particle shortage and increase the number of effective particles.Simulation results show that: compared with APF-TBD and particle filter track-before-detect,OGRAPF-TBD has higher target detection probability and tracking accuracy,and stronger applicability.