Current concentration in a channel region is reduced in a case where diffusion occurs of impurities from an element isolation region. A semiconductor element includes the element isolation region formed on a semiconductor substrate, a source region, a drain region, a gate, and the channel region. The gate is arranged on a surface of the semiconductor substrate between the source region and the drain region with an insulating film interposed between the gate and the semiconductor substrate. The channel region is arranged directly below the gate and between the source region and the drain region and is arranged adjacent to the element isolation region, and has a shape in which a channel length that is a distance between the drain region and the source region is shortened in the vicinity of the element isolation region.