We demonstrate for the first time the remarkable hemostatic performance of a cross-linked graphene sponge (CGS) as a hemostat. The CGS can absorb plasma immediately to form a blood cell layer and promotes subsequent clotting. To improve hemostatic performance, DCGS, TCGS, GMCS, GKCS and related hemostatic sponges were developed by introducing divers interface stimulations. Now the composite sponge can rapidly stop bleeding in approximately 60 s in rabbit artery injury test. Considering the facile preparation, low cost, nontoxicity, and long shelf life of the portable black sponge, the CGS has great potential for trauma treatment.