The electrostatic discharge (ESD) protection apparatus includes a first well, a second well, a first doping region, and a second doping region. The first well is disposed in a substrate having a first conductivity type, wherein the first well has a second conductivity type and the substrate is electrically connected to a first pad. The second well is disposed in the first well, wherein the second well has the first conductivity type. The first doping region is disposed in the second well, wherein the first doping region has the second conductivity type, and the first doping region is electrically connected to a second pad. The second doping region is disposed in the second well, wherein the second doping region has the first conductivity type.