Aiming at the problem of task assignment to multiple UAV on uncertain SEAD mission environment, a method based on interval-valued intuition fuzzy decision making is proposed. The mathematical model of task allocation is constructed, and the uncertain information of UAVs and tasks is represented by interval-valued intuition fuzzy numbers. By using the principle of TOPSIS, the Manhattan distance and hesitancy of the numbers is used to compare the interval-valued intuition fuzzy numbers. Additionally, an improved discrete differential evolution algorithm is used to solve the task allocation problem. The simulation results indicate that the allocation model has good feasibility and the algorithm has good convergence.