Abstract: The principles and features of different metal-ceramic composite coating technologies were reviewed in this paper.As a new technology,cold gas spraying,which is developed in 1980s and easy to prepare thick layer coatings,was emphasized here.Both its principle and research progress were discussed.It was proven that post-treatment technology for coatings,such as laser surface remelting,could highly improve the performances of coatings,especially for cold gas spraying coatings.