Based on a long-term fertilization experiment on “National Long-term Monitoring Station of Fluvo-aquic Soil Fertility and Fertilizer Effects”，five treatments in the positioning experiment were selected as follows:1)no phosphate fertilizer(NK)，2)chemical fertilizer only(NPK)，3)chemical fertilizer plus farmyard manure(MNPK)，4)1.5 times of application rates of chemical fertilizer plus farmyard manure(1.5MNPK)，5)chemical fertilizer plus maize straw(SNPK) . Soil TP and available P(Olsen-P) under different fertilization treatments were determined，and the relationships between the incremental soil TP，Olsen-P and cumulative phosphorus balance were discussed.The results indicated that the soil phosphorus content in NK treatment was deficient every year，while it displayed a surplus state in treatments with phosphorus fertilizer，and the highest phosphorus accumulation were found under 1.5MNPK treatment.Compared with the NPK treatment，phosphorus accumulation under MNPK and SNPK treatments increased by 12.01% and 10.86%，respectively. After 28 years，compared with NPK，the range of TP and Olsen-P increment for SNPK treatment increased by 3.08，55.34 percentage points，respectively，and the TP and Olsen-P contents were the highest under 1.5MNPK treatment.TP and Olsen-P contents under NPK and SNPK treatments were positively correlated with the number of experimental years.TP content under MNPK and 1.5MNPK treatments were positively correlated with the number of experiment years with the annual increase rates of 0.022，0.028 g·kg-1，respectively.The soil Olsen-P contents were increased quickly in the first 13 years，while the Olsen-P contents were relatively stable in the latter 2～3 years，and then showed the decreasing trend with advance of experimental time.Changes of TP and Olsen-P were significantly affected by phosphorus balance.For every phosphorus of 100 kg·hm-2 surplus in the soil，TP increased by 0.04～0.33 g·kg-1，and Olsen-P increased by 1.94～2.97 mg·kg-1，among them，chemical fertilizer combined with organic fertilizer had the highest increase of phosphorus.In general，soil TP and Olsen-P varied closely following the change of soil phosphorus balance.The combined application of chemical fertilizer combined with organic manure or chemical fertilizer with maize straw could enhance crop phosphorus uptake.The Olsen-P and TP increased promoted under long term phosphorus fertilization in the fluvo-aquic soil，and the fastest increase is in the treatments of chemical fertilizer plus farmyard manure.