A new kind of epoxy resin used in prepreg was preprared by taking dicyandiamide as the curing agent,UR500 as the accelerator and M as the flame retardant.The room temperature storage of the resin was more than 30 days and the resin exhibited excellent mechanical properties.The tensile,flexural and impact strength are 66.5 MPa,133 MPa and 10.7 kJ/m².V-0 level is reached during the UL-94 vertical combustion and the limiting oxygen index(LOI) is 33.6%.The results reveal that the resin exhibits self-extinguish properties away from the fire due to the more dense carbon layer after burning by scanning electron microscope and thermogravimetric analysis.