Dissolution behavior of cementite in a spheroidized SK85 high carbon steel during austenitization heat treatment was investigated in this study. Spheroidized SK85 high carbon steel sheet with fine and uniformly distributed cementites was prepared by proper thermomechanical treatment. Average diameter and aspect ratio of spheroidized cementites were 1 ㎛ and 1.6 respectively. Area fraction of the cementies was measured as 12%. Cold rolling was conducted on the sheet with the reduction ratios from 0 to 0.6 to elucidate the effect of cold deformation on the dissolution behavior of spheroidized cementites during austenitization heat treatment. Austenitization heat treatment was carried out on the cold rolled sheets in a dilatometer at temperatures of 800℃ and 850℃ for various time intervals from 5 to 600 seconds. Heating rate was taken to be 10 and 100℃/s and cooling rate was 150℃/s. In the case of undeformed sheet, 80% of cementites were found to disslove in 5 seconds at 850°C, while only 65% of cementites were dissolved even after 40 seconds at 800℃. With cold reduction increased from 0 to 0.4, dissolution rate at 800℃ appeared to increase and further reduction of 0.6 was found to decrease the rate. At the temperature of 850℃, cold reduction has no prominent effect on the dissolution rate and 8085% of cementites were dissolved in 5 or 10 seconds. Quenching from the austenitization temperature of 800℃ revealed the microstructure of very fine pearlite, while the specimen quenched from 850℃ showed the microstructure of martensite and some pearlites.