The invention relates to a method for extract phase phosphoric acid back extraction in the course of extracting wet-process phosphoric acid by an organic solvent method, which comprises steps: in the process of purification, sedimentation, extraction, washing, back extraction and concentration of the wet-process phosphoric acid, surface active agent is taken as stripping agent, the surface activeagent is added into the extract phase of organic solvent extracted phosphoric acid to obtain mixing solution and is inversely extracted under stirring, is heated in the temperature range of 30 DEG C to 100 DEG C in water bath and constant temperature with the rotation speed of 100-200r/min and reaction time of 20-40min, stands and delaminated. The back extraction rate of the phosphoric acid obtained by the method is much higher than the back extraction rate of the phosphoric acid without adding non-ionic surface active agent; without adding non-ionic surface active agent, the back extraction rate of the phosphoric acid which is inversely extracted with deionized water is only 50-70%, and generally, 3-5 times of back extraction is carried out. The method reduces concentrated steam consumption, saves energy by more than 30% compared with the traditional technique taking water as stripping agent, simultaneously simplifies technique process and reduces the operation time of back extraction.