The present invention provides a heat-transfer mechanism of a motor primary, wherein a heat-transfer member having a metallic body is sandwiched between a motor moving member and a bearing member, such that the heat-transfer member separates the bearing member from the motor moving member to prevent direct contact there-between while the heat-transfer member is used as a heat-conducting medium, and therefore, heat energy on the bearing member and the motor moving member can be gathered in the heat-transfer member, and the effect of effectively dissipating, by means of conduction, the heat energy from the motor moving member and from the bearing member driven by the motor can be achieved.