Metal-organic framework Cu-3(BTC)(2), prepared by an easy hydrothermal method, was used as the oxygenbased catalyst in microbial fuel cell (MFC). The maximum power density of Cu-3(BTC)(2) modified aircathode MFC was 1772 +/- 15 mWm(-2), almost 1.8 times higher than the control. BET results disclosed high specific surface area of 2159.7 m(2) g(-1) and abundant micropores structure. Regular octahedron and porous surface of Cu-3(BTC)(2) were observed in SEM. XPS testified the existence of divalent copper in the extended 3D frameworks, which importantly acted as the Lewis-acid sites or redox centers in ORR. Additionally, the total resistance decreased by 42% from 17.60 to 10.24 X compared with bare AC electrode. The rotating disk electrode test results showed a four-electron transfer pathway for Cu-3(BTC)(2), which was crucial for electrochemical catalytic activity. All the structural and electrochemical advantages make Cu-3(BTC)(2) a promising catalyst for ORR in MFC. (C) 2017 Published by Elsevier Ltd.