The development of antibacterial sponges with both high water-absorbing and mechanical properties is highly desirable for attaining efficient hemostasis and closure of noncompressible wounds, but remains challenging. General methods, such as increasing porosity, to improve the water absorption of sponges inevitably compromise their mechanical properties. Herein, a chitin (CT)/quaternized chitosan (QCS) sponge with the desirable properties was fabricated by freeze-drying the chemically and physically dual cross-linked CT/QCS hydrogel with enhanced hydrophilicity. The obtained CT/QCS sponge possessed improved water (5906%) and blood absorption rates (6374%), robust mechanical strength (compressive stress at 90% strain = 0.52 MPa), and rapid water-triggered shape recovery ability (less than 5.3 s). In addition to good biocompatibility, the CT/QCS sponge also showed high