Availability of phosphorus forms of submerged plant in the sediment and soil has been studied using the submerged plant Hydrilla verticillata culturing in different trophic sediments and soil. Different phosphorus forms in sediments and soil were separated by the chemical sequential extraction methods, at the same time the biomass of Hydrilla verticillata, concentrations of phosphorus in overlying water and in interstitial water were also analyzed. Amount of the bioavailable particular phosphorus was estimated by the formula of age available particular phosphorus. The results showed that labile phosphorus (P) and reducible soluble phosphorus (RSP) were the main phosphorus forms for Hydrilla verticillata utilization. The sediment is beneficial for the growth and fade of Hydrilla verticillata at the growth early stage. Phosphorus concentrations of the overlying water and interstitial water were affected mainly by the RSP concentrations in sediments. Phosphorus concentrations of interstitial water in soil were affected mainly by its labile P concentrations. The submerged plant Hydrilla verticillata promoted available phosphorus transforming, and its utilization rate for available particular phosphorus in soil is lower than that in sediments.