The radon exhalation rate and transfer radon velocity between liquid and gas under different temperature and humidity conditions are investigated. The fitting formulas of radon exhalation rate and temperature and humidity are exponential functions, and each exponent is a 2nd-order polynomial. The fitting formula of transfer radon velocity and temperature is Boltzmann function, and the velocity tends to be stable gradually at 25°C. The fitting formula of transfer radon velocity and humidity is exponential function whose exponent is a 2nd order ...