The present invention discloses a wearable signal input apparatus for a data processing system comprising a wearable unit at least having a index finger sleeve and a middle finger sleeve; a position sensing unit located on said wearable unit for detecting a movement of the index finger and generating a corresponding displacement signal; a first and a second buttons respectively located on the index finger sleeve and the middle finger sleeve of said wearable unit for generating button signals; a signal processing unit provided on said wearable unit for receiving said displacement signal and said button signals and converting said signals into signals which are recognizable by a signal processing system; a signal transmission unit connected to said signal processing unit for transmitting said recognizable signals to said signal processing system; an input switch unit provided on said wearable unit and connected to said signal processing unit for turning said signal input apparatus on/off. The present invention may conveniently achieve the switching interoperation with other input devices and improve efficiency of the signal inputs.