The authors demonstrate the mechanisms of the improved performance of the organic photovoltaic (OPV) cells by using an electron-transporting copper phthalocyanine (CuPc) derivative, hexadecafluoro-copper-phthalocyanine (F 16 CuPc) as the anode buffer layer. The power conversion efficiency and long-term lifetime of the OPV cells with 3nm F 16 CuPc as the anode buffer layer are increased by 50% and 165%, respectively, compared to the reference cell. X-ray diffraction analysis suggests that increased crystalline of the CuPc layer is found, leading to increased hole mobility and exciton diffusion length when it is deposited on F 16 CuPc. As a result, a balanced charge carrier transport between CuPc and C 60 , decreased charge carrier recombination probability, and increased exciton dissociation efficiency can be obtained. Meanwhile, the built-in potential of the cell is also increased, which further promotes the extraction of the photogenerated charge carriers and increases the open circuit voltage of the cells. And the prolonged long-term lifetime of the cells is attributed to the suppressed formation of the reactive −O species on ITO surface and the prevented penetration of them into the organic layers.