As one of the civilized centers of the Eastern world, with comprehensive economic, political, and cultural power, China soon spread strong influences outside but directly with the neighboring nations, including Vietnam. One of the ways to spread China's power is based on the business of its own merchants. Due to the changes in historical context, especially the decline of feudal production relations, the risk of invasion of Western colonialism, especially the official invasion of French colonialism since 1858 in Vietnam, the commercial activities of Chinese merchants according to the same characteristics as many previous historical periods have appeared new features bearing the marks of the era. Therefore, researching the mediating role of Chinese merchants in Vietnam during the XVII-XIX centuries will help us to have a more comprehensive view of Vietnam’s history generally and the economic picture of Vietnam, particularly within a fierce historical period.