Abstract: Gob-side entry retaining technology in the thin and medium thick coal seam mining is mature. The key to success lies in whether the mechanical properties of gob-side support system are compatible with mine pressure behavior or not, and has the functions of fire prevention and plugging or not. FSA fast-sealed agents flexible bearing structure supporting body was used in Beimafang Coal Mine 4313 island face along the gob, it made a good supporting effect with complete section, flame retardant and plugging effect, which reduced floor heave and achieved good supporting effect.