Provided is a semiconductor device which can relax the electric field in the junction termination region, and can achieve a high breakdown voltage.The semiconductor device includes an element region (51) and a junction termination region (52). The element region includes: a first semiconductor region (2) of a first conductivity type; a second semiconductor region (4) of a second conductivity type; a third semiconductor region (10) of the first conductivity type; a trench (35) passing through the second semiconductor region and the third semiconductor region and has a bottom surface which reaches the first semiconductor region (2); a gate insulating film (12) formed on the side surface and a bottom surface of the trench; and a gate electrode (8) embedded in the trench. The junction termination region includes: a terminal trench (55) formed in the depth direction from the top surface so as to surround the element region; a gate insulating film (12) formed on a sidewall and a bottom surface of the terminal trench; and a gate electrode (8) embedded in the terminal trench (55). The depth from the top surface of the second semiconductor region (4) to the bottom surface of the terminal trench (55) is 0.9 to 2.0 times the thickness of the second semiconductor region.