Abstract: It was studied on the phosphorus efficiency and Cheng's index under low-P(0.26mg·kg-1) and high-P(80.0mg/kg) soil,with 111 Yunnan improved breeds and 77 Yuanyang(Yunnan) local races included,tring to reveal the phosphorus efficiency difference between indica and japonica,colored rice and colorless rice,and compare the the phosphorus efficiency between improved breeds and local races.The results indicated:① Relative shoot weight,relative root weight,relative total weight and relative tiller ability could be used as ideal indexes to judge the tolerance to the low-Pof different rice genotypes;② All samples showed that local breeds were more tolerant than improved rices to the low-Pstress,the difference was significant;And a combination of four indices(relative shoot weight,relative root weight,relative total weight and relative tiller ability) showed different tolerance to the low-Pstress by different characters like this:indicaindicalikejaponicalikejaponica,coloredcolorless;The tolerance to the low-Pstress decreased by the increasing of Cheng's index;③ In a word,there was a significant negative correlation between Cheng's index and the tolerance to the low-Pstress.And the phosphorus efficiency showed a close relationship with the differentiation of indica and japonica.