Abstract: The machinery manufacturing industry is one of my country's basic industries, and it plays a decisive role in the development of the national economy. To promote the healthy and rapid development of the machinery manufacturing industry, it is necessary to improve the quality of mechanical engineering design and actively apply advanced technology. CAD technology has rich functions, can meet the drawing requirements of mechanical engineering design, and is relatively simple to operate, which can eff ectively improve traditional design methods. This article expounds the content and application advantages of CAD technology, and analyzes the specific application of this technology in mechanical engineering design.