This study was conducted to investigate change of seed dormancy during storage in rice. The result of germination rate observed at different storage duration after harvest indicated that two Japonica rice varieties, Sangpungbyeo and Hwaseongbyeo, tow sare type local varieties, Jakwangdo and Mongeunsare, and a Tongil type rice, Samgangbyeo, showed no dormancy in rice seed harvested at 40 days after heading, However, weak dormancy was found in matured rice seed of Sobaekbyeo and Odaebyeo, and strong seed dormancy was found in Jungwonbyeo, IR-20 and IR-42. Rice seed stored for 30 days after harvest at 2$0^{circ}C$ constant temperature or 25/15$^{circ}C$ of day /night temperature fluctuation showed higher germination rate above 90% in all varieties tested. But germination rate of seeds stored at 4$^{circ}C$ for 30 to 180 days showed varietal difference, higher in rice varieties having weak seed dormancy and lower in strong dormancy varieties. Days to 80% germination and average days for germination were shortened by storage for 30 to 180 days after harvest at 2$0^{circ}C$, 4$^{circ}C$ with RH 40% or day /night 25/15$^{circ}C$ temperature condition in all rice varieties tested, but the degree of acceleration was lower at the condition of 4$^{circ}C$ with RH 40%.