There is a distinct canyon region to the west and a plateau region to the east. The eastern half of the province which consists of undulating low mountains and round hills, is alimes tone plateau with karst scenery and rivers flowing through deep mountain gorges.

In the west, the high mountains and valleys are closely spaced, forming a steep, unusual, and dangerous landscape. The famous Three Parallel Rivers is located here. Yunnan's major rivers flow through the deep gorges between the mountains. These include the Salween and the Mekong River. The rugged, vertical terrain produces a wide range of flora and fauna, and the province has been called a natural zoological and botanical garden.

The average elevation is 1,980 meters. The mountains are highest in the north where they reach more than 5,000 m (16,000 ft.); in the south they rise no higher than 3,000 m (9,800 ft.).