The working environment of the shipboard anti-air missile launcher is harsh and The operating space is narrowness. According to these condition, The traditional nitrogen filling equipment is difficult to meet operating conditions. Portable and automatic nitrogen filling equipment is designed in this paper, which adopts automatic control and intelligent sensor measuring techniques. By this equipment, automatic venting and charging of missile launcher are realized, which can effective improve the nitrogen filling efficiency of the equipment. By the design of multiple alarms, The error operating rate of the weapon equipment is reduced. The equipment has been put into practical use,and the application results show that the equipment has operational advantage, steady performance and strong practicality.