A medicine delivery device includes a main housing having a guide rail in a bottom side thereof, a main control unit with built-in control program mounted in the main housing, a transmission module mounted in the main housing and electrically coupled to the main control unit, the transmission module including a transmission unit, transmission shaft rotatable by the transmission unit and a push rod threaded into the transmission shaft with an axial guide groove thereof coupled to the guide rail for axial displacement upon rotation of the transmission shaft, a push-button unit mounted on the outer surface of the main housing and electrically coupled to the main control unit, and a power supply unit mounted in the main housing for providing the main control unit with the necessary working electricity.