Behavior of microwave-induced (MI) Ar plasma generated from SIC ceramics in flowing Ar containing trichlorotrifluoroethane (CFC113) and the decomposition of CFC113 by MI Ar plasmas have been investigated systematically at atmospheric pressure. The MI Ar plasma can be generated from SiC ceramics even in flowing Ar containing CFC113, O-2, and H2O at atmospheric pressure, irrespective of continuous or pulsed microwave irradiation. The length of the plasma streak was shortened and the top of the plasma streak was broadened, especially by the addition of O-2 The addition of an appropriate amount of O-2 was indispensable for complete oxidation of C atoms in CFC113. It is confirmed that pulsed MI Ar plasmas offer several advantages in decomposing CFC113, as compared to thermal decomposition, with respect to energy consumption, complete oxidation, and concentration of residual partial decomposition products.