Yunnan has a mild climate with balmy and fair weather, but although the growing period is long, there is little arable land. Agriculture is restricted to the few upland plains, open valleys, and terraced hillsides. Rice is the main crop; corn, wheat, sweet potatoes, soybeans (as a food crop), tea, sugarcane, tobacco, and cotton are also grown. On the steep slopes in the west livestock is raised and timber is cut (teak in the southwest). Yunnan's chief source of wealth, however, lies in its vast mineral resources. It is the country's leading tin producer; other deposits include iron, coal, lead, copper, zinc, gold, mercury, silver, antimony, and sulfur.

China is constructing a series of dams on the Mekong to develop it as a waterway and source of power; the first was completed at Manwan in 1993. Road and railroad traffic has been recently improved, and Kunming is now a transportation center; an important railroad runs from Kunming to Hanoi, Vietnam, while transportation to Myanmar is maintained by the Burma Road.

There are many minority groups in Yunnan. From ancient times the Chinese invaders gradually pushed the aboriginal tribes into mountain localities, where today, retaining their distinct languages and culture, they populate eight autonomous districts. The Miao, Yao, Lolo, Lao, Shan, Thai, and Lisu are some of the larger tribes; there is also a considerable Tibetan minority. Yunnan Univ. is in Kunming.

Separated by rugged mountains from the central authority in N China, Yunnan for centuries remained independent. In 1253 it was conquered by the Mongols of the Yüan dynasty, which destroyed the Thai kingdom of Nan Chao established there. Yunnan passed to the Manchus in 1659 and became a province of China under the control of the central government. It was the scene of a great Muslim revolt (1855–72). It was a major center of Chinese resistance in World War II, and in 1950 it passed to Communist control.