Establishing a kind of electric heating system of phase change floor, analysing the stability and comfort through the simulation. Choosing the phase change materials, which the phase transition temperature is 29°C and the latent heat is 188 kJ/kg. The phase change materials used in electric heating floor heating system, comparing the general electric heating floor system, Calculating the floor surface temperature and indoor air temperature. It turned out that the heat storage of phase change floor system will be well, when compared to the common system, indoor temperature changes gently, human comfort higher. Phase change materials stores the cheap electricalheatenergy, and releases during daytime, So as to realize energy conservation and economy .