A motor unit having an insulation member is provided. The motor unit includes rotor cores formed in a radial direction on an exterior circumference of a motor shaft and a slot formed therebetween. Shoes are formed in a rotation direction and an opposite rotation direction of the motor shaft at an outer end portion of each rotor core, and an exposure passage is formed therebetween. A bottom surface is formed proximate to the motor shaft within the slot. Further first and second interior surfaces are connected to the bottom surface and are formed at the rotation direction side and the opposite rotation direction side of the motor shaft within the slot. An insulation member contacts the first and second interior circumferences of the shoes adjacent to the bottom surface and is disposed proximate to at least one portion of the exposure passage.