President Xi, focusing on building a new pattern of all-round opening up to the outside world and promoting the common prosperity and progress of all countries, put forward a major proposal for the construction of the Silk Road Economic Belt and the maritime Silk Road in twenty-first Century. The bay area economy, as an important coastal economic form, is the highlight of the current international economic map, and is a significant symbol of the world's first-class coastal city. The international first-class bay areas, such as New York Bay area, San Francisco Bay area and Tokyo Bay area, are characterized by openness, innovation, livability and internationalization. The Guangdong-Hong Kong-Macao Greater Bay Area has four world-class cities, name Guangzhou, Shenzhen, Hong Kong and Macao, and the Pearl River Delta city cluster. It has an open economic structure, efficient resource allocation ability, strong agglomeration and spillover function and development international communication network plays a core function of leading innovation and gathering radiation. It is an important growth pole for promoting the economic development of the maritime Silk Road and a leader in technological change. With the help of Portugal's geographical position on the maritime Silk Road and market access advantages within the EU system, the Greater Bay Area should further deepen scientific and technological cooperation, improve the ability of scientific and technological innovation of both sides, let the scientific research subjects of the bay area help Portugal's scientific and technological development, and enhance Portugal's scientific and technological position in the EU. From the perspective of the Belt and Road Initiative, combined with the basic situation and cooperation of China, especially Guangdong, Hong Kong and Macau, and the development of science and technology in Portugal, this article explores the technological fields, policy measures that are suitable for scientific and technological cooperation between the two sides, and puts forward corresponding suggestions to contribute to the technological development of China, Portugal and the global economic and social sustainable development.