In the reaction of the atmospheric pressure plasma process, the heat stable process of the atmospheric pressure plasma jet has a direct impact on the removal rate, CF4 is the provider of active F* atom, O2 is important auxiliary gas, and they play an important role in the process. In order to research the rule of the concentration of the 3 parameters upon the atmospheric pressure plasma processing, the atmospheric pressure plasma jet was used for processing and the spectrometer was used to monitor the changes in the process. The experiment indicates that: when the heat is stable, the concentration of the active F* atom essentially remains unchanged; with increasing the concentration of gas CF4, the spectrum of the active F* atom has self-absorption phenomena, so using the atomic emission spectroscopy method to monitor the changes in the concentration of active F* atom generated by CF4 is not completely exact; because O2 can easily react with the dissociation product of CF4, which inhibits the compound of the active F* atom, so in a certain range with increasing the concentration of gas O2, the concentration of the active F* atom becomes strong.