An icemaker in a refrigerator is disclosed, by which heat generated from a heater to detach ice is prevented from being transferred to an inside of the refrigerator. The present invention includes an icemaker body provided to a prescribed position of the refrigerator to make to ice from a supplied water, a heater provided to the icemaker body to generate heat to facilitate detachment of the made ice, and a heater shielding unit provided to prevent the heat generated from the heater from being supplied to an inside of the refrigerator.