The utility model provides a wireless air humidity collection system of solar energy power supply, includes moisture -proof case, humidity sensing element, master control integrated circuit board, antenna and solar panel. The master control integrated circuit board includes digital analog conversion circuit, singlechip, wireless transmission module, low -power source conversion chip and electric capacity energy storage module. The digital analog conversion circuit exports humidity sensing element's analog signal transition to singlechip for data signal, the data signal of digital analog conversion circuit output is responsible for handling and saving by the singlechip. The utility model provides a drawback that exists in the battery powered scheme of tradition, real -time on -line monitoring natural draft cooling tower advances tower air humidity, and data record is accurate, signal transmission is stable, is convenient for arrange the multiple spot simultaneous acquisition simultaneously, will greatly save on -the -spot remote wiring cost, helps improving natural draft cooling tower performance index monitoring level.