Abstract: In order to analyze the fertility expression of one kind of super hybrid rice, we selected the photo-/ thermo-sensitive genetic male lines P88S, two different climatic regions were in Hainan and Hunan. The results showed that: in the same CMS in different climatic regions, there was a big difference in their sensitive period, P88S in Changsha, the sensitive periods in the previous three, i.e.Ⅲ,Ⅳ,Ⅴperiod. In Haikou, there were two sensitive periods, the first sensitive period inⅡ,Ⅲperiod, the second inⅣ,Ⅴ,Ⅴ,Ⅵ,Ⅶperiod. Under natural conditions, in Haikou from May 5 to May 9, the pollen infertility fluctuated from 67.24% to 85.60%. The pollen sterility was greater than 99.50% from 11 May to 18 October; seed-setting rates were all less than 0.50%. In Changsha, CMS P88S in 2010 from July 17 to October 7, pollen sterility was almost all of > 98.0%, only three days except, there were September 9, September 11 and September 13, there were 86.08%, 90.31%, 92.38%. Seed setting rate volatility was relatively large, fluctuated from 0.29% to 9.81%, breeding insecurity.