The present invention provides an inject ion molding machine in which vibrations in a bearing of a motor decrease when a drive shaft is driven. The injection molding machine includes a motor which includes a stator, a bearing which is held to the stator, and a rotor which is rotatably supported by the bearing, and a drive shaft which is disposed on an inner peripheral side of the rotor and rotates and moves linearly by a rotary motion of the rotor, in which the motor includes a biasing member configured to bias the bearing with respect to the stator toward one side in an axial direction.