The response to temperature and photoperiod conditions of the 5460 male-sterile line (Subsp. indica), which was claimed to be a photo period sensitive male-sterile line before, was investigated with two-way completely random design in growth chambers. The fertility of the five control cultivars (lines) were normal at all the six treatments, and the pollen fertility and the self-fertility within paper bags of 5460s were normal only at the daily max. and min. temperature 27/22℃ (weighted meanwas23.5℃) condition regardless of the pbotoperiods tested (12.0 h, 13.5 h or 15.0 h), but unnormal at the 33/28℃ (29.5℃) condition regardless of the photoperiods,it meant that most of the 5460s plants were sterile completely or in a great degree.Analysis of variance of self fertility, of the 5460s showed that difference caused by photoperiod was not significant,while that caused by temperature was very significant (P～0), the interaction between temperature and photoperiod also influenced the fertility significantly (P=1.05%). The results indicated that 5460s would not be a photoperiod sensitive male-sterile line but a “temperature sensitive” one.The actual fertility change of 5460s in Fuzhou in the summer, 1987 and the local climatological data at the same duration were analyzed. It was found that the behaviour of 5460s at the natural condition accorded with the conclusion resulted from experiments under artificial-controlled conditions. The potential value of the temperature sensitive male-sterile rice to theoratical research and breeding practice was discussed.