A thangka (ˈt̪haŋka; Tibetan: ཐང་ཀ་; Nepal Bhasa: पौभा) is a Tibetan Buddhist painting on cotton, silk appliqué, usually depicting a Buddhist deity, scene, or mandala. Thangkas are traditionally kept unframed and rolled up when not on display, mounted on a textile backing somewhat in the style of Chinese scroll paintings, with a further silk cover on the front. So treated, thangkas can last a long time, but because of their delicate nature, they have to be kept in dry places where moisture will not affect the quality of the silk. Most thangkas are relatively small, comparable in size to a Western half-length portrait, but some are extremely large, several metres in each dimension; these were designed to be displayed, typically for very brief periods on a monastery wall, as part of religious festivals. Most thangkas were intended for personal meditation or instruction of monastic students. They often have elaborate compositions including many very small figures. A central deity is often surrounded by other identified figures in a symmetrical composition. Narrative scenes are less common, but do appear.
Thangka serve as important teaching tools depicting the life of the Buddha, various influential lamas and other deities and bodhisattvas. One subject is the Wheel of Life (Bhavachakra), which is a visual representation of the Abhidharma teachings (Art of Enlightenment). The term may sometimes be used of works in other media than painting, including reliefs in metal and woodblock prints. Today, printed reproductions at poster size of painted thangka are commonly used for devotional as well as decorative purposes. Many thangkas were produced in sets, though they have often subsequently become separated.
Tibetan Buddhist painting developed from widespread traditions of early Buddhist paintings which now only survive in a few sites such as the Ajanta Caves in India and the Mogao Caves in China, which have very extensive wall-paintings and were the repository for what are now the earliest surviving Tibetan paintings on cloth.