To promote performance of organic photovoltaic device (OPV), a high-efficiency OPV structure is designed based on local surface plasmon (LSP) technology, which is composed of ITO/P3HT:PCBM/Ag nano-prisms array (ANPA)/Ag film/glass substrate. The ANPA used in this structure can effectively excite LSP and enhance the light absorption efficiency of OPV. The simulation results show that an up to 22-fold light absorption enhancement can be achieved through the parameter optimization of the ANPA. In this paper, we introduced a low-cost and easily-operated technology, poly-styrene spheres (PSs) self-assembly technology, to fabricate the ANPA, and then embedded them into the P3HT:PCBM blend layer. We measured the spectrum of this organic structure, and found a significant light absorption enhancement in the near-infrared waveband due to the excited LSP modes. The experimental results indicate this designed OPV structure together with the self-assembly technology is effective to enhance the light absorption efficiency of OPV, and has a very good application prospect. (C) 2012 Elsevier B.V. All rights reserved.