In order to improve the soil fertility of saline-alkali land in the Yellow River delta, we analyzed the effect of phosphate-solubilizing bacteria on phosphorus conversion.The single factor experiment was used to analyze the phosphorus solubilizing ability of RPB03 strain selected from the rhizosphere soil of Suaeda salsa in the Yellow River delta under the different environmental factors. The results showed that RPB03 strain was named Pantoea vagans, belonging to Pantoea. In the closed culture system, RPB03 strain showed effective phosphate solubilizing ability that the dissolved phosphorus content was exceeding 300mg/L under higher salinity, temperature and alkaline conditions. The results of pot experiment showed that RPB03 strain could effectively promote the conversion of the invalid phosphorus to the available phosphorus in soil (the soluble phosphorus content increased from 0.029 mg/kg to 0.043 mg/kg). Therefore, the strain RPB03 was a kind of effective phosphate-solubilizing bacteria with strong salt and alkali tolerance, which was suitable for survival in the saline-alkali land of the Yellow River delta, and its existence could promote available phosphorus content in the saline-alkali soil.