The second edition of Fundamentals of Mechanical Design is based on the revised “Basic Teaching Requirements for Mechanical Design Courses” formulated by the Teaching Steering Committee for Mechanical Basic Courses in Colleges and Universities of the Ministry of Education. Under the overall plan of China’s “14th Five-Year Plan,” it adheres to the principle of “focusing on the integration of application skills and theoretical knowledge based on theoretical knowledge” and strengthens experimental and practical efforts. Combining with the teaching reform and quality course construction of the university, it is a comprehensive and three-dimensional quality textbook. The book is divided into 14 chapters, focusing on topics such as the degree of freedom of planar mechanisms, planar linkage mechanisms, cam mechanisms and intermittent mechanisms, gear mechanisms, gear trains, gear transmission, belt transmission, chain transmission, connections, shafts, sliding bearings, rolling bearings, couplings, and clutches.