The invention discloses an inclination angle controlling method during the anisotropic wet etching process of silicon oxide. According to the method, a thin layer of silicon oxide medium is deposited on a to-be-etched silicon oxide layer. Through regulating the density and the thickness of the thin layer of silicon oxide medium, the lateral etching speed of the to-be-etched silicon oxide layer can be controlled. Furthermore, the inclination angle of the to-be-etched silicon oxide layer during the anisotropic wet etching process thereof can be controlled. The method is simple in process and easy to realize. When the silicon oxide medium prepared by the above method serves as an etching-resistant mask, an efficient way is provided for further controlling the morphology of a side wall during the etching process of other semiconductor materials.