The core technology of high dehumidification air conditioning system is its high separation rate and high permeability of membrane. The membrane interior consists of low friction water molecular flow channels, when water molecules entering the flow channel, they are arranged in a continuous manner molecule by molecule to generate a capillary phenomenon and, which accelerates the flow-through rate of water molecules. This invention only needs to adjust the vacuum and pressure setting to achieve higher dehumidification performance. The membrane isothermal dehumidification technology allows us to integrate it with heat exchange module to establish an independent temperature and humidity control system. According to theoretical calculation, this system possess a very promising potential in aspect of energy saving. The technology can also be applied to an air water machine to separate clean water directly from air. Small dehumidification module can be applied to gas analysis instruments to reduce moisture pollution and enhance sensitivity.