Passive jamming is the significant pattern of jamming for Fire Control (FC) Radar. A comprehensive model is set up according to the respective characteristics of passive jamming and FC Radar in order to conduct quantitative analysis of FC Radar capabilities against passive jamming; the model is applied under given conditions of passive jamming to work out the FC Radar anti-jamming capabilities. It is therefore of certain applied value since the model accurately reflects real conditions by taking into account various factors affecting the FC Radar capabilities against passive jamming.