PURPOSE: To provide a working table the constantly proper working surface height of which is set without a need for a human engineering knowledge.

CONSTITUTION: A working table l is provided with a motor 5 with the aid of which a top plate 8 is elevated and the motor 5 is controlled by a control unit 9. In response to an input of human body data responding to the height of a worker or the height of a an elbow, work data representing easiness and difficulty of a work, and offset data responding to the height of a work being a work object, the proper height of the top plate is calculated from the data by means of the control unit 9. Further, a control signal responding to the calculated height of the top plate is generated to feed the signal to the motor 5.