The embodiment of the invention discloses a method for removing benzene series in underground sewage. The method comprises the following steps: arranging an extraction well and an injection well; extracting and storing sewage; volatilizing benzene series from the sewage under a vacuum state, treating and discharging the benzene series after reaching the standard; adding an oxidant into the sewagefrom which benzene series are removed, then recharging and the like. The method is used for solving the problems of low benzene removal efficiency, high cost and secondary pollution to the environmentof an existing treatment method. The embodiment of the invention also provides a system for removing benzene series in underground sewage.