Two thermoperiod-sensitive genie male sterile(TGMS) lines of rice, Pei-ai 64s and GD-2s, were grown in greenhouse for multiplication by means of heating from January to May, 1995. When the TGMS lines were in the sensitivity stage of fertility alteration, the mean daily temperature in the greenhouse was controlled at 23 ℃. After heading, their pollen fertility was monitored by dricroscope and the seed setting rates were checked. The results showed that the seed setting rate of Pei-ai 64s reached 50.7%, its individual plant yield was averagely 3.5g. The multiplication of pedigree seeds for Pei-al 64s grown in the greenhouse in winter was successful. It is proved that seed being multiplied in the greenhouse in the winter is a better way to expedite the reproduction of TGMS lines at low critical temperature.