Abstract: An outside back mirror is disclosed which comprises a base plate, a hinge structure and a mirror housing, and is characterized in that, a through hole, retaining sections, metal pieces, and a fitting groove are provided on the assembling plane of the base plate, while a through hole, retaining sections, a groove with a spring hanging groove, permanent magnets, and another fitting groove are provided on the assembling plane of the mirror housing. According to the present invention, the mirror housing is attached firm enough to withstand against any impacts and vibrations, and has a simplified structure and uses small number of components, thereby contributing to saving the manufacturing cost and improving the productivity.