A projection display device comprises a main body cabinet, a projection lens section to which light modulated by a light modulating element entered, and a mirror section for reflecting the light emitted from the projection lens section to a projection plane. A level difference depending on an arrangement shift of the projection lens section and the mirror section is formed on a second side surface facing a first side surface having light projection port of the main body cabinet. Furthermore, the projection display device comprises a level difference correction section for directing the light from the mirror section in a desired direction by correcting the level difference, when the main body cabinet is planed on a plane to be placed, the second side surface facing the plane to be placed.