This paper is based on the new air gap membrane distillation cooling cavity as the object of study for seeking a suitable refrigeration source instead of large, high energy consumption of the refrigerating machine. Study the matching theory of the new air gap membrane distillation components and semiconductor refrigeration, at the same time, making the coupling design.To use forced convection cold dispersion and circulator bath cooling way, under specific conditions test analysis semiconductor cold end temperature variation, explore suitable for semiconductor number and operation conditions of air gap membrane distillation cooling cavity. Research results show that there has a great effect on the semiconductor cold end temperature for cooling circulating water flow rate. Besides also have advantages, such as suitable for long time operation, rapid cooling, good stability and so all. It can be true that semiconductor cold end temperature can reach the desired temperature conditions of membrane distillation cooling cavity, in the conditions of the fan air volume is 600m3/h, room temperature is 24℃, cooling circulating water flow is 700L/h, water temperature is 20℃, input current is 20A. In these conditions the semiconductor cold end temperature is 8.86℃,refrigerating capacity is 112.83W and membrane area is 0.0104 m2. It can be used as the preferred scheme of optimization air gap new membrane component cooling cavity.