[Abstract] As an international comprehensive mega-expo, China International Import Expo is a major decision of China to advance a new round of high-level opening-up, a major initiative to proactively open the Chinese market to the world, and a practical action to support economic globalization and trade liberalization. Based on the market mechanism, reflecting national will, and exercising "government guidance, market operation, enterprise management", it will leverage the unique drive effect of international comprehensive mega-expos to promote the coordinated development of upstream and downstream related industries, and achieve the multiplier effect of guiding the industrial transformation and upgrading of Shanghai districts, Yangtze River Delta cities and even the country's tertiary industry. It will also leverage the spillover effect brought about by on-site gathering of brands and products from around the world at the National Exhibition and Convention Center, namely the large-scale, diversified and concentrated display and transaction of commodities, technologies, personnel, capital, information and other resources within a short period, creating positive externalities on economic and social development of related regions. The research shows that as an imported expo landing in Shanghai and held periodically, its drive and spillover roadmap features a process of formation in Shanghai, radiation to Yangtze River Delta city clusters and Yangtze Economic Belt, and extension to all parts of China and along the Belt and Road. To maximize undertaking of CIIE's drive and spillover effects, Shanghai should seize opportunities to massively introduce characteristic advantageous commodities and services from all countries, take multiple coordinated measures, amplify inter-industry linkage effects, optimize resource allocation, improve innovation environment, encourage sound competition between enterprises, and drive industrial structure optimization and upgrading.