Based on a 15-year long-term fertilization experiment in the fluvo-aquic soil,the effect of different fertilization treatments on inorganic-P forms and their availabilities in wheat rhizosphere was studied by pot experiment.The results showed that the content of Ca-P was higher than those of other forms in all the fertilized treatments,occupied 73.9% of total inorganic P,the total content of other P forms occupied 26.1%.The wheat biomass and P uptake were very low without P application(CK,N,K),and the total content of inorganic P changed very small in the rhizosphere and bulk soils,and the contents of Ca2-P and Ca8-P were very low in all treatments.The wheat biomass and P uptake of NP and NPK were significantly higher than those of PK,and PK significantly increased the content of inorganic P in the rhizosphere and bulk soils compared with N and NP.While combined application of P fertilizer and organic manure,the biomass and P uptake of wheat were significantly increased,and 1.5(M NPK) significantly increased the total and all forms of inorganic P,those of S NPK were not increased clearly.By correlation analysis between OlsenP and inorganic P forms,it was shown that Ca2-P was correlated most significantly with Olsen-P;Ca8-P,Al-P and Fe-P were significant,while O-P and Ca10-P were not significant.