Abstract: The technology of liquid desiccant and solar regeneration is the key technical problems of evaporative cooling in high temperature and humidity region, and the most important thing is the dehumidification/regeneration efficiency. The calculating relationship between the humidity content of in/out air and dehumidification efficiency was established through the experimental measurement. And the relationships of temperature of regeneration heat source to regeneration quality, diffusion coefficient and regeneration efficiency were researched. The results showed that with the regeneration temperature increasing, the regeneration quality, diffusion coefficient and regeneration efficiency were rising. When the regeneration temperature was 104℃, the regeneration quality was 10 g/kg, diffusion coefficient 0.277 cm2/s, and regeneration efficiency 55%. But when the regeneration temperature was lower 50℃, the regeneration cannot work. So the effective temperature regeneration was at least 70℃ in solar energy mixed solution dehumidification system. Based on the Chung model, the calculation formula of dehumidification efficiency in the multistage cross flow dehumidifier was established for the solar energy dehumidification system, and the dehumidification efficiency was 56.8%.This research for greenhouse facilities dehumidifying technology provides a study basic.