In order to improve the credibility of air-attack targets threat assessment, a method on the basis of ANFIS and attack-defence confrontation was presented according to the index system of threat assessment. This method combines fuzzy inference with neural network, comprehensively integrates air-attack target type, attack intention and ship-to-air missile defense capability. The simulation results show that the threat assessment system reflects the mapping rules between threat index and level. Therefore, the method is feasible and effective to provide decision support for air defence operation.