We incorporated gold nanoparticles (Au NPs) in inverted organic photovoltaic devices to enhance the device performance. The photocurrent and fill factors were improved after the addition of Au NPs into the Cs 2CO 3 buffer layer. The photoluminescent measurements revealed a significant increase of light absorption of the photoactive layer. We attribute the improvement to local field enhancement induced by the localized surface plasmon resonance. Further, through the study of the morphologies of the cathode interfaces, we found that the rough surfaces might increase the device resistances. This drawback, however, was overwhelmed by the advantageous plasmonic effects.