In order to solve the problem of the target assignment in corporative engagement of multiple platforms,an algorithm of distributed target assignment based on contract mechanism was put forward.Firstly,the distributed description model based agent was established;secondly,the initialization assignment based on auction contract and the cooperation assignment based on swap contract were introduced to perform the target assignment;finally,the work flow of the system was proposed.It is conclued from the simulation results that the weapon systems of multiple platform can be assigned distributedly and effectively whether in general instance,in the instance of detecting new target or in the instance that the platform damaged.