A high-performance organic photovoltaic heterojunction based on the triplet material, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphineplatinum(II) (PtOEP), is demonstrated and 2.1% energy-conversion efficiency obtained (see Figure). As the exciton diffusion length might be extended greatly, triplet materials have great potential for use in organic and polymer solar cells.