It is critical but remains challenging to make fiber-shaped energy storage systems to satisfy the rapidly developing area of flexible and wearable electronics due to the difficulty in finding high-performance fiber electrodes. Herein, we designed a one-step hydrothermal strategy to synthesize graphene/(molybdenum disulfide) hybrid fiber electrodes with a novel intercalated nanostructure that effectively combined the high electrical conductivity from graphene sheets and high pseudocapacitance from molybdenum disulfide sheets. The intercalated nanostructure also simultaneously provided large ion-accessible surface areas and a high active material content of up to 33.98 wt%. The resulting fiber-shaped supercapacitor exhibited a high specific capacitance of 368 F cm⁻³.