The multi-system weapon assignment of Low,Slow,and Small (LSS) targets is studied.Aiming at the shortcomings of the traditional model when applied in real combat scene,the limiting factors of laser, radio and flexible network weapons in intercepting LSS targets are analyzed,the constraints in space,time,resources and environment are deduced,and the weapon interception weight factor is introduced in an optimized multi-system weapon assignment model for LSS target.Genetic algorithm is employed to solve the model.Finally,through the simulation and comparing the calculation results with that of the traditional model, it is verified that the optimization model established in this paper has higher calculation efficiency,and the assignment result obtained is more feasible and reasonable,which can provide a better solution for the research of multi-system weapon assignment research.