This study was aimed at the production of SiC-MoSi2 composite powders through a high-temperature plasma reaction route. The addition of SiC appears to be the best second phase reinforcement for improving the mechanical properties of MoSi2 material for high-temperature structural application. The in-flight carbonization of MoSi2 powders was carried out in an Ar-H2-CH4 induction plasma process. Using methane in the role as both the powder carrier gas and the "precursor" to react with the MoSi2 powders forming the SiC phase in-situ. Under the experimental conditions employed in this investigation, up to about 8.0 wt. % of carbon was incorporated into the MoSi2 powder particles. The chemical composition, phase content and the microstructure of the composite powder products were examined by XRD, SEM, EDS etc. analysis methods. The reaction mechanisms are discussed in terms of the calculated thermodynamic equilibria.