The invention discloses a method for preparing a FeSe-based superconducting material. The method comprises the following steps: 1, putting mixed powder of iron powder and selenium powder into a vacuum ball-milling tank; 2, performing high energy ball-milling treatment on the mixed powder; 3, pressing the mixed powder to obtain a FeSe-base blank; and 4, sintering the FeSe-base blank, thereby obtaining the FeSe-based superconducting material. According to the method disclosed by the invention, a high energy ball-milling machine is adopted to perform high energy ball-milling treatment on the mixed powder within a relatively short time firstly, after the sizes of original grains of the mixed powder are reduced, a Fe-Se solid solution is obtained, Fe and Se in the mixed powder reach atom-grade mixing, the limit on reaction rate in the dispersion process in the sintering treatment is eliminated, the mixed powder is laminated and is subsequently sintered, thereby obtaining the FeSe-based superconducting material with high superconducting phase content and advantages of small energy consumption, short process, high repeatability and the like.