Abstract: A plasma reactor and a plasma ignition method using the same are disclosed. The disclosed plasma reactor includes at least one magnetic core having a transformer primary winding wound thereon, an AC power supply for supplying AC power to the transformer primary winding wound on the magnetic core, at least one plasma chamber body, at which the magnetic core is installed, to directly induce a voltage in the plasma chamber body through the magnetic core, thereby inducing induced electromotive force in the plasma chamber body, and at least one floating chamber connected to the plasma chamber body via an insulating region, the induced electromotive force from the plasma chamber body being indirectly transferred to the floating chamber. Ignition of plasma is generated in accordance with a voltage difference generated between, the plasma chamber body and the floating chamber, and the ignited plasma is supplied to a process chamber.