The Ming–Hồ War was a military campaign by the Ming Empire of China to invade Đại Ngu (present-day north Vietnam) ruled by the Hồ dynasty. The campaign began with Ming intervention in support of a rival faction to the Hồ, but ended with incorporation of Vietnam into China, marking the start of the Ming province of Jiaozhi.

A few years earlier, Hồ Quý Ly had violently taken the Trần throne, which ultimately led to the intercession of the Ming government to reestablish the Trần dynasty. However, Hồ's forces attacked a Ming convoy escorting a Trần pretender, who was killed during the attack. After this hostile event, the Yongle Emperor of the Ming Empire appointed Marquises Zhang Fu and Mu Sheng to prepare and lead the Ming armies for the invasion of Đại Ngu. The war lasted from 1406 to 1407, resulting in the Ming conquest of Đại Ngu and the capture of the members of the Hồ dynasty.

The former ruling dynasty of Đại Việt, the Trần, had relations with the Ming Empire as a tributary. However, in 1400, Hồ Quý Ly deposed and massacred the Tran house before usurping the throne. After taking the throne, Hồ renamed the country from Dai Viet to Dai Ngu. In 1402, he abdicated the throne in favor of his son, Hồ Hán Thương (胡漢蒼). Eventually, in May 1403, he requested the investiture of his son from the Ming government on the account that the Trần lineage had died out and that his son was a royal nephew. Unaware of the deeds that Hồ had committed against the Tran, the Ming government granted him this request. In October 1404, Trần Thiên Bính (陳添平) arrived at the Ming imperial court in Nanjing, claiming to be a Trần prince. He notified the court of the treacherous events that had taken place and appealed to the court for the restoration of his throne. No action was taken by them until early 1405, when his story was confirmed by an Annamese envoy.

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