An angle measuring method comprising the steps of: forming an original graphic on an original graphic forming face; projecting the original graphic onto a screen so as to form a projected graphic on the screen; and deforming the original graphic so as to turn the projected graphic into a predetermined shape such that a first angle formed, in a first plane orthogonal to a reference installation face for installing the original graphic forming face and the screen, between the screen and a first perpendicular drawn relative to the reference installation face, a second angle formed, in a second plane parallel to the reference installation face, between the screen and the original graphic forming face and a third angle formed, in the first plane, between a second perpendicular drawn relative to the original graphic forming face and the reference installation face are obtained, and an angle measuring apparatus.