Photovoltaic (PV) devices using blend films of poly(methyl phenyl silane) (PMPS) and fullerene (C60) are fabricated, and the effects of various technical parameters during device fabrication on the PV characteristics under AM 1.5G simulated solar light illumination of 100 mW/cm2 intensity are investigated. The PV performance of the devices depends on the mixing ratio of PMPS:C60, the kind of buffer layer, the thickness of the buffer layer, and the thermal annealing temperature of the devices. The devices optimized for the mixing ratio, kind of buffer layer, and thermal annealing temperature exhibit a short-circuit current density (J
SC) of 2.26 mA/cm2, an open circuit voltage (V
OC) of 0.71 V, a fill factor (FF) of 0.35, and a power conversion efficiency (PCE) of 0.57%.