he physiological and growth characteristics, yield formation and dry matter production of 20 mid-season hybrid rice combinations administrated recently were investigated under submergence stress at tillering stage and heading stage. The results showed that: （1）The growth period of mid-season hybrid rice combinations were significantly affected by submergence stress. Under submergence stress at tillering stage, the heading stage of main crop rice and ratoon rice were delayed by 3.25 d and 3.95 d, the maturity stage were delayed by 1.85 d and 2.75 d respectively; however, the maturity stage were decreased by 1.60 d under submergence stress at heading stage. （2）The yields were significantly affected by submergence stress. Compared to the contrast, the yields of hybrid rice combinations with submergence stress at tillering stage decreased by 59.0%, because of the decrease of leaf dry matter, effective panicles and grain number per panicle; the yields of hybrid rice combinations with submergence stress at heading stage decreased by 57.6%, because of the decrease of grain number per panicle and seed setting rate. （3）Strengthen field management to retain the first season rice was better than cutting seedling for growing ratoon rice after 48 h submergence stress at tillering stage, however, planting ratoon rice was a good chance after 48 h submergence stress at heading stage. （4）The submergence tolerance in tillering stage and heading stage is not relevant, the flooding resistance ability should be tested indifferent growth stage in rice production.