An ESD protection semiconductor device includes a substrate, a gate set formed on the substrate, a source region and a drain region formed in the substrate respectively at two sides of the gate set, at least a first doped region formed in the source region, and at least a second doped region formed in the drain region. The source region, the drain region and the second doped region include a first conductivity type, and the first doped region includes a second conductivity type. The first conductivity type and the second conductivity type are complementary to each other. The second doped region is electrically connected to the first doped region.