Nanostructured porous MnO2 film on Ni foam substrate was fabricated via a CV electrodeposited route for the first time. The obtained MnO2 film had a 3D network structure and a high mass loading from 6 to 18mg cm−2. This material achieved a maximum specific capacitance of 2790mF cm−2 at 2mA cm−2 and 864mF cm-2 at 20mA cm−2, and the specific capacitance can be retained above 90% after 1000 cycles at 5mA cm−2. The fabricated AC//MnO2 asymmetric supercapacitor can reach a specific capacitance of 67F g−1 and an energy density of 37.22Wh Kg−1 with its capacitance retention of 80% after 1000 cycles at 2.5mA cm−2.