Aiming at the problems that the traditional obstacle-setting task is not suitable for the joint operation of army, and the efficiency of the obstacle-setting task is low, this paper constructs an evaluation model for the operational efficiency of the equipment formation of engineering corps by using the probabilistic network time parameter calculation method. Based on the analysis of the example, the composite influence coefficients of time and forces consumed by different equipments are calculated under the given time and known obstacles. The calculation results show that the model can provide some theoretical support for the optimization of wartime engineering equipment grouping.