A method for manufacturing a semiconductor device includes: preparing a semiconductor substrate, in which a first semiconductor layer is formed on a substrate; forming a first concave portion in the first semiconductor layer; forming trenches on the first semiconductor layer in the first concave portion; epitaxially growing a second semiconductor layer for embedding in each trench and the first concave portion; forming a SJ structure having PN columns including the second semiconductor layer in each trench and the first semiconductor layer between the trenches; and forming the vertical MOSFET by: forming a channel layer and a source region contacting the channel layer on the SJ structure; forming a gate electrode over the channel layer through a gate insulating film; forming a source electrode connected to the source region; and forming a drain electrode on a rear of the substrate.