In this paper, the influence of oil mist on the tool temperature in cutting is investigated experimentally. The turning of a carbon steel with oil mist applied is performed, and the temperature of the alumina tool at the tool-chip interface is measured using a two-color pyrometer. The tool temperature in dry cutting at a cutting speed of 300 m/min is , but it is when oil mist is supplied. In intermittent turning, the oil mist has more effect on the tool temperature because it is supplied more efficiently to the tool-chip interface. In end milling with the oil mist applied, the tool temperature at the flank face is at a cutting speed of 400 m/min, though in dry cutting it is .