Developing low-polarization and stable cathodes is key to the success of intermediate-temperature solid oxide fuel cells (IT-SOFCs). Here we report a study on the electrochemical performance and stability of a La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF) cathode material by using gamma irradiation approach; with different doses 20kGy, 250kGy and 500 kGy. This is an innovative method; which has an tremendous effect on Morphology and electrical properties. LSCF cathode samples were systematically characterized by X-ray diffraction (XRD), photoluminescence (PL), high resolution transmission electron microscope (HRTEM), and BET surface area analyzer. The occupancy of oxygen vacancies in the samples was conceded by PL studies. Electrical properties was investigated for both un irradiated and irradiated (LSCF) samples at various operating temperatures from room temperature up to 400^oC.This novel study shows that the cathode performance was strongly influenced by particle size, surface area and formation of oxygen vacancies. All physical and electrical properties for LSCF samples were improved by using gamma radiation approach; which has high impact on cell performance.