Chemical vapor deposition (CVD) is a versatile technique for mainly preparing thin films typically used in semiconductor devices and protective coatings. Highly pure and dense self‐standing materials can be also prepared byCVDfollowed by removing the substrate after deposition. Without the substrate,CVDcan form powder or particles in a gas phase. In addition, by changing the wide‐ranged deposition condition ofCVD, it can be employed to discover new materials.CVDcan also be used to prepare highly oriented, anisotropic or porous materials.AsCVDgenerally adopts thermochemical reactions to prepare various forms of materials, it is fundamentally a high‐temperature process; this is sometimes disadvantageous for practical applications. In such cases, auxiliary energy such as plasma and photo (laser) can be employed to accelerate chemical reactions and enable low‐temperature deposition. This chapter mainly describes the preparation of films and various forms of materials byCVDand auxiliary energy‐assistedCVD.