A catalyst enhanced chemical vapor deposition (CECVD) apparatus is provided in which the showerhead and catalyst support are separated from each other. The CECVD apparatus has excellent spacing between the showerhead, catalyst wire and substrate and can be purged to prevent contaminants from forming on parts functioning at low temperatures. The CECVD apparatus comprises a reaction chamber, a showerhead for introducing reaction gas into the reaction chamber, a catalyst wire for decomposing the reaction gas, a catalyst support for supporting the catalyst wire, a substrate on which the decomposed gas is deposited, and a substrate support for supporting the substrate.