Since the emergence of machinery, there is a corresponding mechanical parts. But as a discipline, the machine parts are separate from the mechanical sealtectonics and mechanics. With the development of machinery industry, new design theories and methods, new materials, new technology, machinery parts into a new stage of development. Finite element method, fracture mechanics, elastic hydrodynamic lubrication, optimization design, reliability design, computer aided design (CAD), solid modeling (Ug, Pro, Solidworks, etc.), system analysis and design methodology, etc., have been gradually used in the research and design of mechanical parts. It is important to realize the combination of various disciplines, realize the combination of macro and micro, explore the new principle and structure, and adopt more dynamic design and precise design.