Abstract: The effects of stem-cutting ratooning treatment on the activities of some physiological indexes of photoperiod(temperature)-sensitive genic male sterile rice(PTGMSR)‘Peiai64S’were studied.The results show that the stem-cutting ratooning treatment can increase the content of chlorophyll and enhance the activity of nitrate reductase of the flag leaf.Meanwhile it promotes the accumulation of soluble sugar to panicle and increases the contents of free proline of flag leaf, stem,and panicle.