Abstract: To study the character of P fractions and acid phosphatase in leaf, we conducted a pot experiment of super-low P (25 mg·kg^-1 soil), low P (50 mg·kg^-1 soil) and normal P (75 mg·kg^-1 soil) in P-efficient barley (DH110, DH147) and P-inefficient barley (DH49). Inorganic P concentration was reduced significantly by low P stress, except for insoluble phosphate, in leaves of barley. The nucleic P concentration in upper leaves was higher in P-efficient than P-inefficient barley, but the nucleic P concentration in bottom leaves was lower; only 18.4% to 91.4% of that in P-inefficient barley. The ester P concentration and distribution ratio in bottom leaves was less in P-efficient than P-inefficient barley. However, the ester P concentration was decreased significantly only in P-inefficient barley and was significantly lower than in P-efficient barley. Moreover, the distribution of nucleic acid P and the ester P in P-efficient blades showed a better nutritional status of P in upper leaves and stronger decomposition conversion of soluble organic P in bottom leaves. Under P-deficiency, the acid phosphatase activity in bottom leaves increased significantly and was 1.29 to 1.41 times higher in P-efficient than P-inefficient barley. The P-efficient barley could improve inorganic P transformation from ester-P and nucleic P by enhancing the acid phosphatase activity of lower leaves, which increases the content and ratio of mobility P to improve P-recycling in the late growth stage of barley.