In view of the attack decision-making of fighters with Miniature Air Launched Decoy (MALD) in the process of one-to-one air combat， a new method was proposed based on Chaos Particle Swarm Optimization (CPSO) algorithm.The motion models of the fighter， the MALD， and the target fighter were established.Based on the analysis to air combat capability of the fighter， deceit ability of MALD， and threat level of target fighter， the indicator function of attack decision-making was established.Finally， a model of the attack decision-making based on CPSO algorithm was established.Simulation results show that the new method can make MALD work better and improve the survivability of the fighter.