We report a facile strategy to synthesize a hierarchical core-sheath PANi@MoS2 nanocomposite as an advanced electrode material for high-performance electrochemical capacitor applications. Hierarchical core-sheath PANi@MoS2 nanostructure is prepared in a one-pot synthesis via a hydrothermal redox reaction between ammonium tetrathiomolybdate and polyaniline nanofibers. Structural and morphological characterizations of the as-prepared PANi@MoS2 nanocomposite are investigated by Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements. The obtained PANi@MoS2 electrode displays a good electrochemical capacitance performance with a specific capacitance of 450Fg−1 under 0.5M H2SO4. More importantly, the core-sheath structure of PANi@MoS2 electrode enhances the structural stability during the electrochemical process and thus improves the electrochemical cycling stability of the electrode significantly, which retains 80% in specific capacitance after 2000 charge/discharge processes.