The “15th Five-Year Plan Period” is a critical period for building up China’s strength in finance through high-quality financial development and thereby promoting high-quality economic growth. In this process, a strong international financial center, as the center of the “six key core financial elements” of a financial powerhouse, shoulders strategic responsibilities such as optimizing the allocation of global financial resources, enhancing international financial discourse power, and enhancing national competitiveness. Based on the overall requirements of building up China’s strength in finance, the connotation, mission, and typical characteristics of a strong international financial center can be defined in three dimensions: function orientation, service orientation, and quality orientation. Specifically, a strong international financial center should possess developed financial markets, complete financial autonomy, a prosperous financial ecosystem, significant international influence, and strong financial innovation vitality. China’s solid economic foundation and well-established financial system provide important support for building such a center. At present, Shanghai and Hong Kong have laid a solid foundation for building a strong international financial center. However, further progress is needed in four key areas: RMB internationalization, financial infrastructure, financial business environment, and international competitiveness. Therefore, we should continue to promote high-level financial opening-up, improve financial infrastructure, and optimize the financial business environment. Following the guiding ideology of enhancing Shanghai’s competitiveness and influence as an international financial center and consolidating Hong Kong’s status as an international financial center, it is necessary to strengthen the linkage between Shanghai and Hong Kong, thereby promoting the construction of a strong international financial center and better serving the “dual circulation” pattern of economic development.