An 8 years long-term experiment was conducted to explore the effect of reduced 20% chemical fertilizer combinedwith22.5，30，37.5 and 45 t·hm -2 Chinese milk vetch and chemical fertilizer conditions on the forms of inorganic phosphorusand rice yield in south Henan province.The no fertilization treatment was used ascontrol.Results showed that the contents of Al-P，Fe-P，Ca -P，O-P，available phosphorus，alkali -hydrolyzed nitrogen，available potassium and rice yield weresignificantly increased under all the aforementioned treatments compared with thecontrol.Moreover，compared with theapplication of chemicalfertilizer，the treatment of reduced 20% chemical fertilizer combined with various amounts of Chinese milk vetch increased the content and proportion of Fe-P，Al-P and Ca-P，but decreased the content and proportion of O -P.The results of correlation，path and stepwise regression analyses showed that Fe -P was the most effective phosphorussource， Al-P and Ca-P was the slow-release phosphorus source and O-P was the non-effective phosphorussource.The Al -P，Fe-P， Ca-P had an significant or extremely significant correlation with riceyield，soil inorganic phosphorus and alkali -hydrolyzednitrogen.The rice yield of 20% reduction of chemical fertilizer combined with Chinese milk vetch treatment increased by 24.26%～ 26.01% and 3.75%～ 5.38% compared with no fertilization and chemical fertilizertreatment，respectively.The highest rice yield was the treatment of 30 t·hm -2Chinese milk vetch combined with 20% reduction of chemicalfertilizer.Considering the availability of soil phosphorus，rice yield and soil nutrients，the effect of applying 20% reduced chemicalfertilizer combined with 22.5～ 30 t·hm -2 Chinese milk vetch was better.