Abstract: A large-output injection/measurement mechanism of an injection molding machine, which uses measurement and injection servo motors as its drive source. A plurality of ball screws are rotatably provided between front and rear plates of the injection molding machine and are coupled to the injection servo motor. Ball nuts engaged with the plurality of the ball screws are fixed on a pressure plate. The pressure plate is coupled to the measurement servo motor through a spline shaft and a rotational drive pipe spline-coupled thereto. The spline shaft is fixed on a screw sleeve rotatably fixed to the pressure plate. A screw fixed to the pressure plate is driven by the servo motors, thereby performing injection and measurement of a molding material.