Abstract: Phosphate solubilizing microorganisms (PSM) play important roles in the phosphorus cycle, which could transform insoluble phosphate into soluble phosphate and increase the availability of phosphate fertilizer. In this study, the phosphate solubilizing ability of 9 phosphate solubilizing microorganisms were detected by the method of phosphomolybdate-blue spectrophotometry and 3 of them were selected with better phosphate solubilizing ability, then every 2 of this 3 strains were co-cultivated in different inoculation proportions, the contents of dissoluble phosphorus in liquid cultures were determined and the phosphate solubilizing abilities were compared. The results indicated that the best phosphate solubilizing ability during the fermentation process was obtained in the culture medium when B.thuringiensis HDBP2 and B.cereus HDBP5 were cocultivated at the ratio of 2:1, and the soluble phosphorous content could reach 90.25 μg/mL. Furthermore, the pqqE gene of B.thuringiensis HDBP2, B.cereus HDBP4 and HDBP5 which could promote the dissolution was cloned to further illuminate the phosphate solubilizing mechanism in molecule biology. The co-culture of B. thuringiensis HDBP2 with B.cereus HDBP4 could enhance their phosphate solubilizing abilities.