Wide-body mouse and mouse widening device

The invention discloses a wide-body mouse and a mouse widening device. A first side face and a second side face of the wide-body mouse make contact with the inner side faces of a thumb and a little finger of a relaxed hand. A left key is arranged below an index finger (right hand) or a ring finger (left hand) of the relaxed hand, a middle key and a roller are arranged below the middle finger, a right key is arranged below the ring finger (right hand) or the index finger (left hand), and the five fingers are in a relaxed state when the hand is placed on the wide-body mouse; a third side face and a fourth side face of the mouse widening device make contact with the inner side faces of the thumb and the little finger of the relaxed hand, the thumb and the little finger are in a relaxed statewhen the hand is placed on the mouse widening device, so that the fatigue, aching pain and lesions of the thumb, the little finger and related muscles are relieved. The thumb and the little finger cancontract inwards and expa