Due to the large specific surface area and potential redox sites, metal organic frameworks (MOFs) are considered as a promising electrode material for supercapacitors. However, the low electrical conductivity of MOFs impedes their application in supercapacitors. Here, the NiCo-MOF/acetylene black composites were facily fabricated by an ultrasonic method, in which acetylene black was uniformly distributed between NiCo-MOF nanosheets and formed a conductive network, thus improving the electrical conductivity of NiCo-MOF as well as hindering their aggregation. The as-obtained NiCo-MOF/acetylene black composites exhibit high specific capacitance of 916.1 F g−1, remarkable rate capability and cycling stability compare to the pure NiCo-MOF. In addition, an asymmetrical supercapacitor were also constructed, which achieved a maximum energy density of 33.84 Wh kg−1 at a power density of 750 W kg−1 and good cycling stability with 85.25% of initial capacitance after 5000 cycles.