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Ceramic matrix composites (CMC) constitute a category of composite materials widely used in the aerospace industry as they satisfy the thermal, chemical and mechanical requirements of a good composite material with the drawback being in the high processing costs. Chemical vapor deposition is a process long known for its importance in aerospace and structural applications. Chemical vapor deposition can be used to develop thin interfacial coatings on fibers, which are reinforced in to a matrix according to the application. The interfacial layers are useful for preventing reactions between the fibers and the matrix material at high temperatures. Interfacial coatings can also deflect crack propagation once the composite is put into service. This work focuses on developing a suitable gas phase and surface kinetics model for obtaining the deposition profiles in the chemical vapor deposition of pyrocarbon on silicon carbide fibers at the given conditions of temperature, pressure and feed rate. The model uses an existing gas phase mechanism (National Institute for Standards and Technology and Gas Research Institute). There are combinations of species in the gas phase, but all of them do not lead to the deposition of pyrocarbon. This raises a question as to which of them would affect the rate of deposition and why. For the given conditions of temperature, pressure and flow rate and from the information available in different literature sources acetylene is assumed to be the major depositing specie of pyrocarbon. Also, the gas phase mechanism was modified to simplify and suit the needs of the given conditions. The importance behind modeling the surface kinetics is that it could help understand the actual process in the formation of pyrolytic carbon. The mechanism of the pyrocarbon deposition could be important in knowing the type of carbon being deposited, which is of utmost importance in its applications. The modeling data is validated by means of using data obtained from experiments.