An ice-making assembly for a refrigerator, which can effectively separate ice from a tray and a power transmission assembly for transmitting power to the tray are provided. The power transmission assembly includes a body unit defining an exterior of the ice-making assembly and a plurality of gear teeth protruding from an outer circumference of the body unit. Each of the gear teeth includes a first end portion protruding from the body unit by a predetermined distance and a second end portion further protruding from the body unit than the first end portion. According to the embodiments, even when the water is infiltrated into the power transmission assembly and frozen, the frozen ice can be removed in a direction by the above-described structures of the gears.