The change characteristic and the relation of chlorophyll content, photosynthesis rate, SOD activity, POD activity, malondialdenhyde content and soluble protein were studied in the condition of lowly applying fertilizer under the convention management condition through field plot experiment. The results indicated that the change of docking-stubble winter wheat flag leaf chlorophyll, photosynthesis speed, SOD and soluble protein content assume the single peak tendency along with the increasing amount of Ploughing Corn Straw under Soil; the change of POD and MDA assume the single valley tendency along with the increasing amount of Ploughing Corn Straw under Soil in the condition of Lowly applying fertilizer under the convention management condition, The effects of Ploughing corn Straw under Soil on the wheat flag leaf senescence mainly are to influence the level of protection enzyme, particularly the POD. Under this test condition, the rate of 9000 kg wheat straw /hm2 is best on each anti\|senility target, the value of anti\|senile membership function and the output; the rate of 15000 kg wheat straw /hm2 is worst. Therefore, lowly applying fertilizer under the convention management in this area, ploughing corn straw under soil had the most favorable effect at the rate of 9000 kg wheat straw /hm2.