A method of manufacturing a semiconductor device capable of preventing a cut portion from becoming chipped when dicing. The method of manufacturing a semiconductor device includes preparing a semiconductor wafer having an upper surface (first surface) including a plurality of device regions and partition regions for dividing the plurality of device regions, and a lower surface (second surface) opposite from the upper surface (first surface), forming upper layer wires on the device regions of the upper surface (first surface), etching the semiconductor wafer from a side of the lower surface (second surface) to form a through hole through which the upper layer wire is exposed, and to form a groove in a region of the lower surface (second surface) corresponding to the partition region of the upper surface (first surface), and dicing the semiconductor wafer to form individual device regions.