Cobalt vanadates and their composites have drawn tremendous attention because of their outstanding cycling stability. Rational design of 3D micro/nano-structures using a facile strategy has a promising potential for supercapacitor applications. Herein, we propose a 3D porous Co2V2O7-3 center dot 3H(2)O microflowers electrode as a cathode for pseudocapacitor via a simple co-precipitation technology. The resultant Co2V2O7-3 center dot 3H(2)O with microflowers structure exhibits a high specific capacitance of 351 F g(-1) at a current density of 1 A g(-1), and an ultralong cycle lifetime with 103% capacitance retention after 30,000 cycles. An asymmetric supercapacitor device is also successfully assembled consisting of Co2V2O7-3 center dot 3H(2)O cathode and rGO anode. The optimized ACS device with a potential window of 0-1.5 V delivers a high energy density and an excellent cycle lifetime. These superior electrochemical properties will render the 3D porous Co2V2O7-3 center dot 3H(2)O microflowers material as an attractive material for promising application in energy storage systems.