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. The gate set includes at least a first gate structure, a second gate structure, and a third gate structure.