Three-dimensional interconnected honeycomb-like porous carbon (IHPC-800) is successfully fabricated via activated and graphitized plane tree fluff with the aid of Co2+ and KOH in a synthetic process at 800 °C. The as-prepared IHPC-800 exhibits advantageous structural features for application in supercapacitors (SCs), including interconnected pathways, high specific surface area (1154 m2 g-1), large pore volume (0.78 cm3 g-1), heteroatom doping, and full graphitization. This material possesses a very high charge storage capacity with a specific capacitance of 493 F g-1 in 2 M H2SO4 in a three-electrode system at a current density of 0.2 A g-1. It exhibits excellent cycle stability, even over 10000 cycles with a capacity retention of more than 96%. The energy density of 42.8 W h kg-1 is also verified with 1 M LiPF6 in EC/DEC as the organic electrolyte at a power density of 299 W kg-1. The excellent electrochemical performance and facile effective synthesis of bio-derived carbon materials point to an economical and feasible strategy for the large-scale production of high performance SCs.