To provide the mold thickness adjusting apparatus and nozzle advance and retreat driving control apparatus of an electromotive injection molding machine capable of performing adjustment of mold thickness or the movement of a nozzle to a large extent within a short time and capable of also accurately performing the fine adjustment of a position.

Power is supplied to a mold thickness adjusting motor M1 and a nozzle forward and rearward moving motor M2 through an inverter 3. The rotational speed of the mold thickness adjusting motor M1 and that of the nozzle forward and rearward moving motor M2 are adjusted by the PWM control due to the inverter 3 and the moving speed of a rear platen or that of a nozzle is selectively changed. The shortening of a moving required time by high speed movement and the accurate positioning work by low speed movement can be achieved at the same time.