Abstract: An overview is presented of the development of researches on residual stresses in thermal spray coatings. It includes some new ideas on the origins of the residual stresses, the main experimental techniques for measurement of the residual stresses, the analytic models for determining the distributions of the residual stresses, and their effects on interface toughness. Finally, some prospective research topics in this field, which are interesting both in science and engineering, are given.