Currently, although some progress has already been achieved, the complex and high-cost synthetic route, and low electrochemical properties of supercapacitor still restrict its practical application. Here, NiMoO4/NiO nanoflowers material with a high specific surface area grown on a nickel foam conductive substrate is successfully synthesized via a facile and efficient method, which exhibits an excellent capacitance of 10.3 F cm(-2) (1982.3 F g(-1)), a good rate capability, and a remarkable cycling stability (capacity remain 98.6% after 3000 cycles). In addition, a novel asymmetric supercapacitor with excellent energy density is also fabricated via the NiMoO4/NiO nanoflowers as the positive electrode and a piece of active carbon as the negative electrode in 3M KOH electrolyte. The optimized asymmetric device operating at 1.7 V also offers a high energy density and an outstanding long-term cycling stability. These impressive results suggest that such NiMoO4/NiO nanoflowers can pave the way for designing and developing next-generation high-performance storage systems.