To solve the problem that the information dynamics in constant weight summing is not flexible enough in air-combat situation assessment,a dynamic variable weight method is proposed for the situation assessment in close-range air combat.Based on the advantage function,the evaluation index system is improved by adding the air-combat capability index.Moreover,according to the Bayesian theory,the situation type is determined in real time,the characteristics of air-combat situation changes are integrated,and the weight of the evaluation index is dynamically adjusted according to the variable weight theory.The feasibility and effectiveness of this method in air-combat situation assessment are verified by the simulation experiments with real air combat data.Simulation results show that the dynamic variable weight evaluation method can effectively prevent the problem of poor information dynamics caused by constant weight summing.