In order to understand the conversion efficiency of closed storage phosphorus to available phosphorus in woodland soils, taked the populus euramevicana forest grey fluvo-aquic soils in Gushi County of the Huaihe River Basin as an example, the release of total phosphorus (TP) in grey fluvo-aquic soils and various forms of phosphorus, including TP, inorganic phosphorus (IP), organic phosphorus (OP), Fe/Al-P and Ca-P, were carried out at different low molecular organic acid, acid concentration and reaction time. The results show that the TP release rate of malic acid, citric acid and oxalic acid increased by 180%, 161% and 217%, respectively. The average activation rate of TP in soil by malic acid and citric acid is over 164%, while oxalic acid showed activation effect only at medium concentration. All of the three low molecular weight organic acids can effectively promote the release and activation of phosphorus in grey fluvo-aquic soils, and the release is closely related to the type and concentration of organic acids and the experimental treatment time, and the activation is also significantly related to the type and concentration of acids. The results of this study can provide scientific basis for the rational application of p fertilizer and the improvement of soil available P.