Fertility index has been evaluated using s taging-sowing experimental data on sacked self-fruitful rate,air temperature and sunshine hours for 13 new genic male steril(GMS) rices from three geographical ecological places(Sanya of Hainan,Wuhan of Hubei and Guiyang of Guizhou).The ecological features of the index are investigated both by grading light-temperature and by applying a quantitative fertility model respectively and their practical importance are discussed finally.