An improved plasma lighting system is provided which includes a bulb filled with both metal halide and mercury as primary light-emitting materials. By maintaining an operating pressure of the metal halide at between approximately 0.1 and 10 atm, and an operating pressure of the mercury at between approximately 30 and 150 atm, a point source of light characteristic and a spectrum characteristic of the emitted light is improved. Therefore, the plasma lighting system can be applied to an optical system that requires a point source of light, and can maximize lighting efficiency to provide improved overall emission characteristics.