According to operational principle of a terminal sensing ammunition(TSA) and attack characteristics with "pinpoint and spread area" combination against group target, utilizing analytical method of firing effectiveness and using hit probability, damage probability, expected number of damaged targets, rounds consumption as evaluation indicator, then building a kind of an analytical model on firing effectiveness evaluation of a TSA against group armored target. By comparing with Monte Carlo method, the model ensures both evaluating accuracy and requirements of fast, and it can usually be used to evaluate firing effectiveness of a TSA in fire control system and command system with high requiring real-time.