Abstract: In order to investigate the effect of ultra-fine on phosphate powder application, as well as the phosphate solubilizing bacteria on ultra-fine phosphate powder, a pot experiment was conducted to investigate the poplar growth, phosphorous uptake and soil phosphorous content as affected by ultra-fine rock phosphate powder, phosphate powder, calcium superphosphate and dissolved phosphate microbe. Results showed that compared with rock phosphate powder, ultra-fine rock phosphate powder improved the poplar seedling height, diameter and biomass significantly, and phosphorous content and phosphorous uptake was increased by 8.96% and 22.85%, respectively. There was no significant difference of poplar growth and biomass between calcium superphosphate and ultra-fine rock phosphate powder. However, compared with calcium superphosphate, ultra-fine rock phosphate powder decreased poplar phosphorous content and phosphorous uptake by 10.05% and 11.97%, respectively. Ultra-fine rock phosphate powder co-applied with dissolved phosphate microbe increased bacteria, actinomycetes amount and the total microorganism amount by 41.89%, 28.57% and 41.53%. However fungus amount was significantly decreased by 31.19%. Ultra-fine rock phosphate powder co-applied with dissolved phosphate microbe had little effect on poplar growth, phosphorous uptake and phosphorous content in soil. Compared with phosphate power, ultra-fine rock phosphate powder increased acid-soluble phosphorous and available phosphorous by 53.27% and 45.35%. Acid-soluble phosphorous and available phosphorous was increased by 15.68% and 13.60% in ultra-fine rock phosphate powder than that in calcium superphosphate. Total phosphorous was highest in phosphate power, but no significant different was found of water-soluble phosphorous in all the treatments. In short, ultra-fine rock phosphate powder improved the poplar growth, increased phosphorous uptake and utilize, which was benefit the long-term supply of phosphorous in soil. However, Ultra-fine rock phosphate powder co-applied with dissolved phosphate microbe had no effect on phosphorous supply ability in soil.