Traditional NiCo₂S₄ vulcanization process requires high-temperature and high energy supply, and has disadvantage of low conductivity. In this study, an environmental friendly vulanization method was utilized to prepare unique NiCo₂S₄@ACF core-shell heterstructure materials with activated carbon fiber (ACF) as skeleton at room temperature. NiCo₂S₄@ACF composite electrode material owns layered structures, which can effectively expand contact area with electrolyte, improve electron transmission path, and better create electrochemical performance. Specific capacitance of NiCo₂S₄@ACF composite electrode materials reached 1541.6 F/g (678 μF/cm²) at the current density of 1 A/g. In addition, the asymmetric supercapacitors (ASC) device fabricated with NiCo₂S₄@ACF as positive electrode and ACF as negative electrode exhibited energy density as high as 49.38 Wh/kg at the power density of 800 W/kg, and preeminent cycle stability up to 90.28% after 2000 cycles. All these data demonstrated that NiCo₂S₄@ACF is a promising potential application in the field of high-performance supercapacitors in the future.