The multi-tube anti-aircraft rocket launcher possesses all the advantages of traditional rocket launchers， especially exhibiting an irreplaceable advantage against new-type low， slow， and small aerial targets compared to other air defense weapons. In terms of target tracking and shooting， the continuous rotation of the barrel brings many new and urgent problems to be solved. Based on the analysis of the effect of barrel rotation on the structural design and overload of the weapon system， initial disturbance， ballistic stability， as well as its influence on the ballistic and shooting elements， this paper focused on simulating and calculating the changes in initial velocity and ballistic elements caused by different barrel positions and rotational speeds. The magnitude and pattern of initial velocity and ballistic deviations under different conditions were obtained， and the correction of the differential method and deviation method， as well as their accuracy and applicable conditions， were presented. Additionally， regarding the determination of shooting elements under the condition of barrel rotation， corresponding treatment methods and suggestions were given. This study provides theoretical and practical guidance for further optimization of the weapon system design， modeling of the fire control system， and shooting command methods.