Establishing a n-level site selection-allocation model that considers multiple types of products, multiple types of facilities at the same level, and the same type of facility can handle multiple types of products, and considers 4 uncertain scenarios, and finally designing an improved beetle-genetic algorithm to solve it.The improved algorithm takes the genetic algorithm as the basic framework, the hybrid beetle algorithm enhances the local search ability, and the adaptive operator is introduced to balance the local search ability and the global search ability. The example test verifies the effectiveness of the BAS-AGA algorithm. An example of a railway project verifies the rationality of the ME-LAP model, and it is found that the logistics cost can be reduced by appropriately increasing the number of facilities and scientifically selecting the location of the facility, thereby reducing the total cost.