Zhongshan is one of the famous ancestral hometowns for overseas Chinese in Guangdong Province. The number of overseas Chinese whose ancestry can be traced to Zhongshan exceeds 800,000, scattered in 87 countries and regions around the world, including Hongkong, Macao and Taiwan region. They are playing an important role of bridge in facilitating the exchanges between Zhongshan and the outside world.

Zhongshan actively carries out friendly exchanges with the people worldwide, which contribute to its development in economy and various social causes. Zhongshan established sister-city relations with Moriguchi City of Japan and Honolulu City of USA respectively in 1988 and 1997.