Abstract: A field experiment was carried out to explore the effects of commercial organic fertilizer combined with reduced 10% and 20% chemical fertilizer on soil fertility and rice yield in south Henan province. The series of commercial organic fertilizer application was 750, 1 125, 1 500 kg/hm², and 100% chemical fertilizer as the control. The results showed that treatment with 1 125 kg/hm² of commercial organic fertilizer could reduce 10% chemical fertilizer and increase rice yield,treatment with 1 500 kg/hm² of commercial organic fertilizer could reduce 20% chemical fertilizer and increase rice yield. Compared with the control,the rice soil available N was significantly increased with commercial organic fertilizer applied amount increased, available P and available K increased with commercial organic fertilizer applied amount increased; But only available N content was increased when applied chemical fertilizer, available P was significantly increased under 1 500 kg/hm² of organic fertilize condition, available K was not significantly affected by chemical fertilizer applied amount. So, combined application of commercial organic fertilizer and chemical fertilizer could reduce the chemical fertilizer application amount, reduce the non-point source pollution load, and rationally use of commercial organic fertilizer．

Key words: commercial organic fertilizer, chemical fertilizer, soil nutrient content, rice yield