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Nitrogen-containing carbon sphere with hierarchical porous structure is obtained through a facile thermostabilization and carbonization method of biomass-derivative sodium lignosulfonate. The synthesis route we proposed is cost-effective and environment-friendly without additional nitrogen precursor, activation or templating agent. The as-prepared carbon spheres exhibit high specific surface area of 1255–1939 m 2  g −1 and moderate surface nitrogen content of 1.14–1.66 at.%. When assembling into supercapacitors with 7 M KOH aqueous solution as electrolyte, the carbon sphere shows superior gravimetric specific capacitance up to 276 F g −1  at 0.1 A g −1 , high gravimetric energy density of 7.8 Wh kg −1 and power density of 6.2 kW kg −1 , together with unprecedented cycling stability (99.5% capacitance retention after 10000 cycles). Notably, in 1 M SBPBF 4 /PC organic electrolyte, the carbon sphere based supercapacitor presents impressive gravimetric energy density of 34.3 Wh kg −1 and power density of 9.4 kW kg −1 . These outstanding electrochemical performances suggest that the as-prepared porous carbon spheres should be a promising candidate for the field of energy storage. [ABSTRACT FROM AUTHOR]