In this paper, the authors summarized briefly the retention of phosphorus by soil constituents. Roles of soil.microorganisms, plant roots, mycorrhizae and earthworms in the enhancement of plant availability of soil phosphorus are reviewed. The mobilization of soil phosphorus by soil biota involved mainly solubilization of insoluble inorganic phosphorus by excretion of protons and organic acids, and hydrolysis of organic phosphorus by phosphatases. The processes of phosphorus mobilization were regulated by the equilibrium between soil phosphorus supply and plant P demand. In the last part, possibilities of alternatives of P fertilizers are discussed. It was suggested that by increasing soil biota population and activity soil phosphorus supply could be in sychronization with plant phosphorus demand.