Constructing flexible hybrid supercapacitors is a feasible way to achieve devices with high energy density, high power density and flexibility at the same time. Herein, flexible asymmetric hybrid supercapacitors are fabricated with blow spun activated carbon fibers. Owing to the highly effective conductive network, abundant nitrogen doping, optimized pore-structure and surface chemical properties of the carbon fibers, the as-prepared flexible hybrid supercapacitor shows outstanding energy and power performance (98 W h kg⁻¹ (0.3 mW h cm⁻²) @ 400 W kg⁻¹, 9 W h kg⁻¹ @ 34 kW kg⁻¹), as well as excellent cycle stability with 93% capacitance retention after 4000 cycles.