The enhanced photoelectric conversion is demonstrated in nanostructured glass substrates for a-Si thin film solar cell. The nanostructured glass substrates were fabricated using nanosphere lithography and RIE technique. The nanostructure substrates provide antireflective and light scattering characteristics, which enhance the broadband light absorption, especially in near-infrared range. Finally we demonstrate the patterned glass substrates (nipple shape arrays) which are useful in light absorption of a-Si thin film solar cell. Compared to a flat glass substrate cell and Asahi-U glass substrate cell, the power conversion efficiency enhancement achieved 48.4% and 3.1%, the Jsc enhancement achieved 51.6% and 8%.