A waste gas treatment method with the application of nano-bubbles and a waste gas treatment system using the same are provided. The method includes the steps of: feeding waste gas to an accommodating space; flowing a predetermined body of water in the accommodating space and generating the predetermined body of water including nano-bubbles; directing the waste gas mixed with the predetermined body of water including the nano-bubbles to a swirling unit; and discharging the treated gas waste. The predetermined body of water including the nano-bubbles is mixed with the waste gas so that the nano-bubbles of the predetermined water and the waste gas may be sufficiently subjected to the cavitation effect and supercritical water oxidation, and harmful substances such as sulfur dioxide, nitrogen monoxide and other nitrogen oxides, volatile organic compounds, heavy metals and the like, of the waste gas may be removed.