In a switching element, a first region that is exposed on an upper surface of a semiconductor substrate, a second region that is exposed on the upper surface of the substrate and extends to below the first region, and a third region that is formed below the second region, are formed on the substrate. A trench is formed in the upper surface of the substrate. A gate electrode has a first portion that extends from a depth of the first region to a depth of the third region at at least a portion in the trench formed in an area where the first region is exposed, and a second portion that is formed to a depth of the second region, and does not reach the depth of the third region, at at least a portion in the trench formed in an area where the second region is exposed.