Abstract:[Objective] The objectives of the study are to investigate the characteristics of soil phosphorus fractions on Heilu soil and its relationships with AM fungi colonization under no-till and stubble retention, in order to understand the phosphate use efficiency in rain feed agricultural system.[Methods] Total phosphorus, available phosphorus and phosphorus fraction and arbuscular mycorrhizal(AM) fungi colonization were determined using classical methods for maize crop under 4 tillage managements:conventional tillage, tillage +stubble retention, no-till, no-till +stubble retention in the Loess Plateau.[Results] After nine-year conservation tillage implementation, the content of P in soil layer of 0-5 cm increased. Compared to conventional tillage, the fraction of H2O-P, NaHCO3-Pi and NaOH-Pi was increased by 84.6%, 85.2% and 56.6%, respectively, under conservation tillage. Labile phosphorus(H2O-Pi, NaHCO3-Pi) and potential labile phosphorus(NaOH-Pi) accounted for 11.4% and 4.5% of total inorganic phosphorus. The total phosphorus showed a significantly positive correlation with available phosphorus and phosphorus fraction. Compared to conventional tillage, the AM fungi colonization increased by 20.8% and 16.5% under no-till manage ment.[Conclusion] The content of soil phosphorus was significantly improved under no-till and stubble retention, and the AM fungi colonization had a positive response to no-till.