The condition of fertilizer input and nutrient balance of farmland,especially for the difference of vegetables and grains production,in Taihu watershed were analyzed through more than 700 questionnaire and statistical data.The result showed that the nutrient budget of vegetables were much higher than that of grain crops such as rice and wheat.Although vegetable crops' sown area was only 30% of the total sown area,its' application of phosphorous had accounted for more than 50%.Phosphorous was one of the key factors of eutrophication of lakes,and the sown areas of vegetables were increasing,so its affect for the water surroundings may not be ignored.