A multi-target tracking algorithm based on multi-model is proposed to solve uncertainties in real environment.The algorithm uses dual threshold method to ensure real-time performance and tracking accuracy. The method firstly preliminary determines the targets associated with the measurements, and then tracks these targets. The algorithm also determines the flight conditions according to the target state estimation. Different method are used in accordance with different flight conditions to improve its robust and real time performance. The measured data verifies the efficiency of the algorithm when tracking targets.