An ESD protection device. The ESD protection device is incorporated with a gap structure in a laterally diffused metal oxide semiconductor (LDMOS) field effect transistor, isolating a doped region and a field oxide region. When a parasitical semiconductor controlled rectifier (SCR) of LDMOS is turned off, ESD current is discharged distributively through several discharge paths, avoiding ESD current focus in a signal narrow discharge path and the danger therefrom.