For the uncertain factors in the fire allocation process of air and missile defense problem, the uncertainty theory is used to deal with the uncertain factors in the problem, and an uncertain multiobjective dynamic weapon target assignment model is proposed. In order to deal with the above model, a multi-objective evolutionary algorithm based on decomposition is proposed, which adds the displacement mechanism of firefly algorithm and uniformly randomly adaptive weights mechanism. Then, the simulation results show that the proposed algorithm has good convergence and distribution uniformity for solving multi-objective optimization problem. Lastly, using the algorithm to solve the above model, the results verify the rationality of the model.