Abstract: In order to study the stability and the kinetics of the dissolution and diffusion of potassium salt in the lower troposphere of the solar pond type potassium salt hot solution tank,a solar pond type potassium salt hot solution tank was constructed in the laboratory to detect the solution density,temperature and potassium ion concentration in operation.The experimental results show that the existence of solid potassium salt layer at the bottom enhances the stability of the solar pond type potassium salt hot solution tank,and the kinetic equation of K⁺ dissolution and diffusion in the operation of the solar pond type hot solution tank is obtained.