Solid oxide fuel cells (SOFCs), which are an electrochemical device to generate power with high efficiency, free of pollution, and non-regional restrictions, have attracted extensive attention. Traditional SOFC works at temperatures above 800 °C, restricting its commercialization. Thus, lowering the working temperature becomes necessary and interesting. Perovskite La1-xSrxCo1-yFeyO3-d (LSCF) was demonstrated as a candidate of SOFC cathodes working below 800°C, because of the high electron-conducting and proton-conducting properties. Meanwhile, the reported results confirmed that F ion doping in perovskite could further improve the stabilization. Here, the electronic structure, oxygen absorption on the (100) surface, formation energy of oxygen cavity, and activation energies for oxygen ion migration in the bulk of F doped LSCF were calculated based on density function theory(DFT). The results reveal that the F doping in the LSCF can improves the oxygen absorption and oxygen ion migration, further promoting the activity of cathode.