In a p-type substrate region of a semiconductor substrate, an n-type source region, an n-type drain region, a p-type body region having an impurity concentration higher than an impurity concentration of the p-type substrate region, a p-type body contact region having an impurity concentration higher than the impurity concentration of the p-type body region, and an n-type drift region having an impurity concentration lower than an impurity concentration of the n-type drain region are formed. A gate electrode is formed on the semiconductor substrate via a gate dielectric film. The semiconductor substrate includes a first region and a second region that are alternately disposed in an extending direction of the gate electrode. A width of the p-type body region overlapping with the gate electrode in the second region is smaller than a width of the p-type body region overlapping with the gate electrode in the first region.