There are provided a semiconductor device having a drain region making a BLDD structure withstandable against a high voltage, sufficiently suppressing a hot-carrier deterioration, and having a high ESD withstandable characteristic, and a method for manufacturing the same. A semiconductor device is formed including a MOS transistor having a source region and a drain region both formed in a semiconductor substrate, and a channel region formed therebetween. At this time, the concentration of holes emitted form P-type impurities injected into the channel region and contributing an electrical conduction is lower at a side close to the drain region than at a side close to the source region. The drain region includes a drift region into which N-type impurities are injected. The drift region extends toward the channel region from the drain region except a nearby area to the surface of the semiconductor substrate.