Mechanical strength and moisture resistance of a multilayer interconnect structure is to be improved. A semiconductor device includes a circuit region and a seal ring region formed around the circuit region, on a semiconductor substrate. The seal ring region includes a plurality of interconnect layers including interconnect lines and a plurality of via layers including a plurality of slit vias stacked on one another, and a pitch between the slit vias in at least one of the via layers (lower or middle layer) is different from a pitch between the slit vias in other via layers (upper layer).