Abstract: By taking steam stimulation of Qi-40 block as an example,by applying CMG numerical simulation software,the base model of steam drive has been established,and the impacts of various factors on development effects have been analyzed.The results indicate with the gradual increase of the positive rhythm reservoir permeability coefficient,the recovery degree and oil-steam ratio increase.When the permeability coefficient of variation is over 0.7,the recovery degree and the oil-steam ratio decrease.With the gradual increase of the positive rhythm reservoir permeability coefficient,the recovery degree and oil-steam ratio decrease.At the steam breakthrough,with the increases of dip angle,the recovery degree decreases,with the increases of the barrier thickness,the recovery degree and oil-steam ratio decrease.Regardless of whether there is the compartment or not,then devel-opment effect is the best when 1/3 position has been shot.When the plane permeability anisotropy is stronger,the development effect is poorer.When the steam injection stratified series are more,the development effects are better.