In the past, Vietnam was impacted by numerous epidemics, particularly during the Nguyễn Dynasty from 1802 to 1883. Based on data from the Đại Nam Thực Lục (1961) (The Veritable Records of the Great South), this article investigates the frequency and nature of these epidemics, identifies the types of common diseases at that time, and explores the underlying causes of these outbreaks. The study further examines the Nguyễn Dynasty's strategies for managing these health crises. During these outbreaks, the dynasty faced significant challenges, with frequent epidemics leading to high death rates, widespread social disruption, and economic decline. The dynasty's primary preventive measures, heavily reliant on spiritual practices like prayer, highlight the limited medical understanding at the time and the constraints of its socio-political framework. However, there was a progressive shift towards the incorporation of Western medical innovations, particularly in the vaccine approach to treat diseases like smallpox. This transition not only marked a critical evolution in the local healthcare approach but also set the stage for more systematic medical advancements in Vietnam during the colonial period (1884–1945).