A gas generating system for health use is provided, including a hydrogen-oxygen gas generator and an atomized/volatile gas generator. The hydrogen-oxygen gas generator has a first casing. The first casing accommodates an electrolysis device for electrolyzing water in order to produce a gas mixture of hydrogen and oxygen. The atomized/volatile gas generator has a second casing, the second casing accommodates a gas mixing camber coupled to the electrolysis device to receive and combine the gas mixture of hydrogen and oxygen with water vapor, an atomized medicine, a volatile essential oil or any combination thereof in order to produce a healthy gas for a user to inhale.