A semiconductor device includes a SiC layer that has a first surface and a second surface, a first electrode in contact with the first surface, a first SiC region of a first conductivity type in the SiC layer, a second SiC region of a second conductivity type in the SiC layer and surrounding a portion of the first SiC region, a third SiC region of the second conductivity type in the SiC layer and surrounding the second SiC region, the third SiC region having an impurity concentration of the second conductivity type lower than that of the second SiC region, and a fourth SiC region of the second conductivity type in the SiC layer between the second SiC region and the third Sic region, the fourth SiC region having an impurity concentration of the second conductivity type higher than that of the second SiC region.