The utility model provides an electronic device which comprises a tray rack and a body. The tray rack is internally provided with a slide block which is provided with locking holes. The body is detachably mounted on the tray rack. The body is provided with locking pins which cooperate with the locking holes. The lower end of each locking pin is provided with a locking projection. When the body is mounted on the tray rack, the locking projections make the slide block slide from an initial position to a detachment position because of contacting with the edge of the locking holes, and furthermore make the slide block return to the initial position after the locking projections are inserted into the locking holes, thereby making the locking projections contact with the lower surface of the slide block.