Abstract: The extraction technology of sapoin from legume of Gleditsia longoleguminosa was established, which was an endemic plant in the Dupangling Natural Reserve. The results showed that: by a serials of single-factor experiments and L16(43) orthographic experiments, the extraction conditions were optimized: the legume powder of Gleditsia longoleguminosa was leached by water with 4 folds of its weight at the first time, the subsequent was kept on 2 folds, the leaching time was 8.0 h, the temperature was 70℃, and the leaching frequency was 4 times in total. Under these conditions, the total sapoin extraction yield could reach up to 29.67%. This research offered an important experimental reference for further developments and utilizations of Gleditsia longoleguminosa.