57 rice varieties mainly planted in the middle and lower reaches of Yangtze River were used to study the mechanism of differences in phosphorus utilization efficiency（PUE） among rice varieties.Hydroponic culture was used to screen phosphorus efficiency.The selected phosphorus-efficient and phosphorus-inefficient rice varieties were used to analyze differences in growth，yield formation，absorption and utilization of phosphorus，the activity of acid phosphatase and expression level of related genes with experiments including hydroponic culture，soil pot，and field plot.The results showed that the phosphorus efficient and phosphorus inefficient variety was identified through screening as Quanyou 879（39#） and Changliangyou 8（21#）.The architecture of root system and biomass of phosphorus efficient variety were better than those of phosphorus inefficient variety under both +P and -P treatments，with significantly higher plant height，total surface area and volume of roots，number of root tips，and dry weight of roots and shoots.The effective number of spikes，spike length，thousand-grain weight，seed setting rate，and grain yield of phosphorus efficient variety were higher than those of phosphorus inefficient variety.The absorption and utilization of phosphorus in phosphorus efficient variety was significantly higher than that in phosphorus inefficient variety.The accumulation of phosphorus in roots and shoots，the absorption of phosphorus，use efficiency and utilization index of phosphorus in phosphorus efficient variety were all significantly higher than those in phosphorus inefficient variety.The expression level of OsPHR2，OsmiR399，OsPT6，and OsPAP10 genes in roots of phosphorus efficient variety under -P condition was higher than that of phosphorus inefficient variety.The activity of acid phosphatase in both roots and root surface of phosphorus efficient variety under both +P and -P treatments was significantly higher than that of phosphorus inefficient variety.It is indicated that the excellent architecture of root，stronger absorption capacity and utilization ability of phosphorus，the higher ability of releasing organic phosphorus into inorganic phosphorus to improve the phosphorus availability to plants are important characteristics of phosphorus efficient variety.