A plasma lighting system comprising a storage unit for storing duty ratios of first and second switching signals according to each material within a bulb by an experiment, a controlling unit for detecting an optimal duty ratio from the storage unit and outputting the first and second switching signals with the same phase corresponding to the detected duty ratio, and a converting unit for converting a direct current voltage into an alternating current voltage consisting of a positive square wave and a negative square wave according to the first and second switching signals, and a method for controlling the same.