The working principle of the plasma organic waste gas purifier is to use a high pressure generator to form a low temperature plasma under the action of a large number of electrons with an average energy of about 5 ev, the organic waste gases, such as benzene, toluene and xylene, which pass through the purifier, are transformed into various active particles, which combine with O _ 2 in the air to form low molecular harmless substances, such as H _ 2O and CO _ 2, so that the waste gases are purified.