Cellulose paper (CP)-based asymmetrical thin film supercapacitors (ATFSCs) have been considered to be a novel platform for inexpensive and portable devices as the CP is low-cost, lightweight, and can be rolled or folded into 3D configurations.However, the low energy density and poor cycle stability are serious bottlenecks for the development of CP-based ATFSCs.Here we developed sandwich-structured graphite/Ni/Co2NiO4-CP as positive electrode and the graphite/Ni/AC-CP as neg-ative electrode for flexible and high-performance ATFSCs.The assembled ATFSCs exhibit large volumetric Csp, high volumetric energy density, high volumetric power density, and excellent cycle stability.This study shows an important breakthrough in the design and fabrication of high-performance and flexible CP-based electrodes and ATFSCs.