The political significance of the integration and development of Hong Kong, Macao and the mainland is first reflected in promoting national unity and national security. As a special administrative region of China, Hong Kong can achieve closer economic and trade ties between Hong Kong and the Mainland, enhance the internal and external connectivity of the Mainland, and effectively safeguard national unity and security. Secondly, the integrated development of Hong Kong, Macao and the Mainland can promote mutual benefit and common development. Hong Kong has advantages and resources in finance, trade, science and technology, culture and other fields. Cooperation with the mainland can form stronger partners, promote industrial upgrading and complementary development, and jointly explore domestic and foreign markets. Third, the integrated development of Hong Kong, Macao and the Mainland will help to strengthen "one country, two systems", the autonomy of Hong Kong and Macao and maintain the uniqueness of Hong Kong. The development support and cooperation of the mainland to Hong Kong and Macao can help Hong Kong and Macao get out of the predicament, enhance the local economic strength and maintain their unique characteristics and cultural heritage. Generally speaking, the integrated development of Hong Kong, Macao and the Mainland is an important attempt of China's development model, which can promote the country's long-term stability and prosperity and realize the maximum play of the principle of "one country, two systems". At the same time, it also needs the wisdom and efforts of Hong Kong, residents and all walks of life in the Mainland to promote the success of integrated development.