Abstract: For the purpose of researching the effects of different exogenous P inputs on the secretion of hydrocarbons from Typha angustifolia roots under As contaminated sediment condition, adopting indoor soil simulation experiments to determine the effects of different exogenous P inputs on the types and concentrations of hydrocarbons in the roots of T. angustifolia under As contaminated sediment. The results showed that the exogenous P input significantly promoted the types and concentrations of hydrocarbons secreted by the roots of T. angustifolia under the As contaminated sediment; the common hydrocarbons in the roots of T. angustifolia were dominated by simple chain normal alkanes, while the special hydrocarbons was centered on the chain branched paraffins; the high concentration of exogenous P input had the most significant effect on the concentration of hydrocarbons under the As contaminated sediment condition; the types and concentration of hydrocarbons presented significantly positive relationship between plant root As concentration and root tolerance.