Abstract: The outgassing characteristics of material is an important parameter for choosing materials in a vacuum system. In this paper,we will research the outgassing characteristics of two materials in a vacuum environment. We use the hole conductance method to measure outgassing rates of the samples at room temperature,baking temperature and after cooling conditions. At the same time,the quadrupole mass spectrometer is used to measure the mass spectrum of the samples at different conditions. The results show that the outgassing rate of the two materials will increase followed by decrease when they are baked,and decrease when pumped. Meanwhile,the mass number 69 is detected in the barking progress,which means that FEP and PFA can release gas containing fluoride.