Abstract: This article is a brief review of Professor Hsue-Shen Tsien's thoughts on Engineering Sciences from the author's perspective. Topics covered are what are engineering sciences, the importance and role of engineering sciences, the strong emphasis on application, basic trainings of engineering scientists and Tsien's application of these ideas in running the Institute of Mechanics. It is the author's view that the mainstream for the development of mechanics in China should follow the route charted by Tsien.