The article discusses how the ethnic groups and cultures in Yunnan during the Qin and Han Dynasties evolved over time. Before Emperor Wu of the Western Han Dynasty, Yunnan had various social stages from primitive tribes to slavery. After Emperor Wu, Yunnan became part of the Han Dynasty, leading to a mix of ethnic groups with the Han nationality and the transition to a feudal society. The cultures in Yunnan also progressed from the Bronze Age to the Iron Age during this period. The unification of the Southwest area had a significant impact on the economic and social development in Yunnan.