A method for manufacturing a nanowire comprises: a first victim (11) is deposited and grown on the upper surface of a substrate (10); a first spacer (12) is deposited and grown along a number N of outer surfaces of the first victim (11); the substrate (10) is subjected to anisotropically etching by employing the first spacer (12) as a mask; the first spacer (12) is removed to obtain a first group of semiconductor fin rays (13); the etched part of the substrate is filled with a filler (14); a second victim (16) is deposited and grown on the upper surface of the filled substrate (10); preset cross angles are formed between the a number Y of outer surfaces of the second victim (16) and various semiconductor fin rays (13) in the first group of semiconductor fin rays respectively; a second spacer (17) is deposited and grown along the number Y of outer surfaces of the second victim (16); and the filled substrate (10) is subjected to anisotropically etching by employing the second spacer (17) as the mask, so as to obtain the nanowire (19).
