Bioremediation research of Pb-contaminated soil was studied by the P-solubilizing characteristic of phosphate solubilizing bacteria, The effect of theSfermentation liquid added amount and total phosphorus content of soil on the soil bioremediation was studied, the mechanism of lead immobilization was studied preliminary by determining the content of olsen-p, NH4NO3 extractable Pb and pH, combined with the results of X ray diffraction analyses. When the added content of target bacterial fermentative solution reached 150ml/kg, the target bacteria can survive in the soil; when the soil total phosphorus reached 1g/kg, the content of NH4NO3 extractable Pb reduced to 4mg/kg and the content of olsen-p increased to 19mg/kg; the analysis of lead speciation indicated that a shift from the exchangeable fractions and carbonate bound lead to residual lead, the results the of XRD analysis showed that the pyromorphite (Pb5(PO4)3Cl) was the main product of residual lead, which is one of the most stable compounds of Pb in soil.