A mold heating/cooling structure for a mold configured with a die base and an insert, comprising: a heat insulating layer, disposed surrounding a die impression of the die base for insulating the heat conduction between the die base and the insert; a magnetic powder layer, disposed against the heat insulating layer; a coil, being disposed on the magnetic powder layer in a manner that it is circling from the outside in toward the center of the magnetic powder layer; and a cooling plate, configured with a plurality of second fluid channels provided fro a fluid to flow therein. With the aforesaid structure, the insert can be heated directly by the coil the it is subject to a high-frequency current, and the heated coil as well as the insert can be cool down with high efficiency as soon as the fluid is fed into the second fluid channels.