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Despite many strong and tough hydrogels have been fabricated according to the energy dissipating mechanism, they usually lack high resilience due to the presence of large hysteresis. Herein, poly (N-vinylpyrrolidone) grafted cellulose nanocrystal (CNC-g-PVP) was used as special multifunctional physical crosslinkers to fabricate tough and highly resilient nanocomposite hydrogels.CNC-g-PVP with varying loading was incorporated into chemically crosslinked polyacrylamide (PAM) networks by in-situ radical polymerization to give PAM/CNC-g-PVP nanocomposite hydrogels. Robust cooperative hydrogen bonds existed between the surface-grafted PVP chains and the PAM matrix, which could rupture to dissipate energy upon deformation and recover instantly on the removal of stress. This unique energy dissipating mechanism led to excellent mechanical performance of the hydrogels. Their tensile elastic modulus, toughness, and compressive strength are 1.4-1.8, 2.1-3.0, and 1.44-2.73 times of pure PAM hydrogel, respectively. Moreover, the hydrogels exhibit low hysteresis, high resilience (ca. 97%) under cyclic tensile loading-unloading and good recovery of hysteresis (ca. 90%) under cyclic compressive loadingunloading.