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Arched structures have increased in importance over the last few years due to their high efficiency in bearing loads. This paper introduces arched ribs to the classical re-entrant honeycomb (RH) as reinforced structures, and then its energy absorption is improved by simultaneously utilizing the reinforced structures and the auxetic deformation of RHs. Herein, the in-plane crashing response of reinforced RHs (RRH) under different impact velocities is investigated with finite element methods verified against the quasi-static compression experiment of 3D-printed RRH specimens. By introducing arched structures, the deformation of RHs becomes more stable and regular, and two plateau stresses are produced in the stress-strain curves of RRHs. Benefiting from the stacking deformation of RRHs and pure compression characteristic of catenary arches, the second plateau stress of all-reinforced RHs (ARH) is 3.8 times higher than the first one. Two plateau stresses of ARHs are derivated theoretically with a relative error of less than 7 %. Furthermore, a parametric study is performed to explore the effect of impact velocities, thicknesses, and the height of arched ribs on the crashing response of RRHs. The present investigation paves a new way toward strengthening the energy absorption of conventional honeycombs. [ABSTRACT FROM AUTHOR]