The invention relates to the field of modeling and simulation, This paper presents a decision method of autonomous firing of companion artillery company which is suitable for 'man is not in the loop'combat simulation, the method comprises the steps of judging the received enemy information, The method comprises the following steps of: judging shooting conditions, sorting targets to be shot, judging direct aim shooting and issuing instructions, determining shooting tasks (interviews), determining damage indexes, determining permissible shooting duration, sorting bomb types, determining bomb types and ammunition consumption, determining firing speed, issuing shooting instructions, and the like. The invention is a military simulation technology, which basically conforms to the general operational use principle and flow of the companion artillery company. The method model decided is simple in calculation and easy to be programmed, and has good application prospect in the operational simulation, especially in the large-scale operational simulation.