To provide a semiconductor device in which an interval between first wells can be shortened by improving a separation breakdown voltage between the first wells and a method for manufacturing the same. A semiconductor device includes a first conductivity type semiconductor substrate 1, second conductivity type first wells 2 and 3 disposed on a surface layer of the semiconductor substrate 1 with a predetermined interval between them, a first conductivity type second well 4 disposed between the first wells 2 and 3 on the surface layer of the semiconductor substrate 1 and having an impurity concentration higher than that of the semiconductor substrate, a first conductivity type third well 5 at least disposed below the second well 4 in the semiconductor substrate 1 and having an impurity concentration higher than that of the semiconductor substrate 1 and lower than that of the second well 4, and a first conductivity type fourth well 11 at least disposed below the third well 5 in the semiconductor substrate 1 and having an impurity concentration higher than that of the semiconductor substrate 1 and lower than that of the second well 4.