Abstract: Stem stimulation has been carried out by a large number of heavy oil reservoirs in China and the research indicates that the injection of steam medium with high temperature,high pressure and high PH value into reservoirs will lead to a series of changes: mineral dissolution,clay transformation,new minerals and precipitation fouling. Through numerical simulation and physical simulation,the variance regularity of reservoirs in steam stimulation of Wangzhuang oilfield has been revealed. The simulation results will provide useful guidance for steam stimulation of heavy oil reservoir.