Abstract: The Yield of rice hybrid seed preduction was obviously fluctuated(ranging from 580.5 to 3024.0kg/hm2)in Putian county during the past decate. The main reason was that the setting percent-age of female parent sharply different in various years,ranging from 11. 25%to 40. 87%. The correla-tive analysis between the yield of hybrid seed and its components as well as meterological factors showed that the factors including average temperattire,relative humidity and other weather conditions during rice heading and blooming phases had greatly effected on the allogamous setting percentage of female parent.The setting percentage would markedly decreased if florescence occured under low temperature(daily temperature lower than 25℃), arid(relative humidity lower than 70%),and plum rains(more than 3 days) or typhoon condition. The above unfavourable factors were the main restrictions in increasing and stablizing the yield of hybrid seed in Putian County.Concerning the statistical meteorological materials and the long time weather reports(from 1～9 months),we try to find out the favourable time to safe blooming. That is the basic measure of increasing and stablizing the yield of hybrid seed production.