Abstract: Based on the mechanism of parallel spring system, theoretical and finite element models of honeycomb with parallel design (HPD) were created based on the concept of functional gradient. The effects of graded coefficient on the in-plane mechanical properties of HPD, including deformation mode, plateau stress and energy absorption, were discussed. The results show that variation of graded coefficient can influence the deformation modes of HPD only under dynamic compression. When the graded coefficient is relatively large, parallel design can improve the plateau property of HPD. Meanwhile, the energy absorption of HPD is also improved. This research provides deep insight into the in-plane properties of HPD with different graded coefficients.