A mouse is provided. The mouse includes a casing, a circuit board, a micro switch base, and a micro switch. The casing includes a button. The circuit board is disposed in the casing. The micro switch base is disposed on the circuit board, and includes a plurality of first openings and a plurality of second openings. The micro switch is fixed on the micro switch base through at least one of the first openings, and electrically connected to the circuit board through the first openings or the second openings.