A microfilm projection apparatus is disclosed which is usable for a plurality of zoom lenses having different magnification ranges from each other. In the zoom lenses attached, the zoom lens selected from the plurality of zoom lenses to be used is identified. A plurality of specific magnifications corresponding to each zoom lens are memorized. When the zoom lens is set in place, the specific memorized magnifications corresponding to the selected zoom lens are indicated. The magnification of the zoom lens is set to the desired magnification designated from the specific magnifications.