Desk capable of expanding desktop

The desk comprises a desk panel and a supporting block, side desk plates are fixedly connected to the left side and the right side of the desk panel, a desk cabinet plate is fixedly connected to the middle of the supporting block, and a strip-shaped mounting plate is fixedly connected to the upper portion of the back face of the supporting plate. One end of the strip-shaped mounting plate is connected with two first rotating arms through rotating shafts and bolts, the ends, away from the strip-shaped mounting plate, of the two first rotating arms are connected with first moving plates through rotating shafts and bolts, and the other end of the strip-shaped mounting plate is connected with two second rotating arms through rotating shafts and bolts. The ends, deviating from the strip-shaped mounting plate, of the two second rotating arms are connected with second moving plates through rotating shafts and bolts. By arranging the first moving plate and the second moving plate, the desk is provided with an additio