An ESD protection device is provided, which includes a P-type doped region, an N-type doped region, a first P+ doped region, a first N+ doped region, a second N+ doped region and a third N+ doped region. The N-type doped region is located in the P-type doped region. The first P+ doped region connected to a pad is located in the N-type doped region. A part of the first N+ doped region is located in the N-type doped region and the residue part thereof is located in the P-type doped region. The second and the third N+ doped regions are located in the P-type doped region and outside the N-type doped region, and are respectively electrically connected to a first power rail and a second power rail. In addition, the second N+ doped region is located between the first and the third N+ doped regions.