A wireless mouse includes a mouse housing, a printed circuit board assembly assembled in the mouse housing, and an antenna mounted on a front end of the printed circuit board assembly. The front end of the printed circuit board assembly defines two fastening holes spaced from each other along a direction perpendicular to a front-to-rear direction. The antenna has a substantial long-strip radiating portion. Two opposite ends of the radiating portion are bent rearward and then downward to form a hook portion and a feed portion which are respectively hooked in the corresponding fastening holes to make the radiating portion transversely mounted over the front end of the printed circuit board assembly. The feed portion is electrically connected with a feed circuit of the printed circuit board assembly.