A solenoid valve includes a valve portion and a solenoid portion. The valve portion has a sleeve and a valve body. The solenoid portion includes a tubular coil portion, a magnetic yoke having a side surface portion and a bottom portion, a columnar plunger, a shaft, a stator core having a core shaft hole for sliding the plunger in the axial direction, and a base portion having a base shaft hole. In a radial thickness of the sleeve, a thickness of a part corresponding to an end outer peripheral surface is smaller than a thickness of a sliding portion of an inner peripheral surface of the sleeve, which is a portion on which the valve body slides.