Abstract: For understanding the response characteristics of physiological process and yield of spring maize to drought stress,a field experiment with continuous no-water complementing was conducted from filling to mature stage of spring maize "Danyu 39".In the meantime,main variables associated with photosynthesis including net photosynthetic rate (P_n) and transpiration rate (T_r),photo response parameter,water use efficiency (WUE) and yield factors were observed and calculated as well as their response characteristics to drought stress were investigated.The results indicate that P_n,T_r,WUE and maximum net photosynthetic rate (P_nmax) are decreasing with the duration of drought prolonging after flowering.During the 15th to 27th day of water controlling,the decrement rates for P_n and T_r vary from 50.0% to 75.1% and 71.7% to 83.6% under the light intensity of 1200 μmol·m^-2·s^-1,and those for WUE and P_nmax expand from 21.7% to 47.9% and 50.9% to 73.2%,respectively.In addition,the drought stress also induces significant decreases of 11.6% and 23.2% for hundred-grain and stalk weight of maize.However,the length and thickness of maize cluster as well as the ratio of grain to stalk do not vary significantly,while the radio of bare-tip and plant grain weight demonstrate a non-significant increasing and decreasing trend,respectively.Besides,a reduction rate of 11.7% for maize yield is caused by the drought during the studied period.