Provided is a nanowire photovoltaic cell (1) including a semiconductor substrate (2) and a plurality of nanowire semiconductors (4) and (5) having a PN junction. The semiconductor substrate (2) and the nanowire semiconductors (4) and (5) are composed of one single crystal. The manufacture method of the nanowire photovoltaic cell includes a step of coating a part of a surface of the semiconductor substrate (2) with an amorphous film (3), and a step of developing a crystal of a material identical to that of the semiconductor substrate (2) through epitaxial growth on the uncoated surface of the semiconductor substrate (2) to form the plurality of nanowire semiconductors (4) and (5).