Wisteria (also spelled Wistaria) is a genus of flowering plants in the pea family, Fabaceae, that includes ten species of woody climbing vines native to the eastern United States and to China, Korea, and Japan. Aquarists refer to the species Hygrophila difformis, in the family Acanthaceae, as Water Wisteria. Some species are popular ornamental plants, especially in China and Japan.

Wisteria vines climb by twining their stems either clockwise or counter-clockwise round any available support. They can climb as high as 20 m above the ground and spread out 10 m laterally. The world's largest known Wisteria vine is in Sierra Madre, California, measuring more than 1 acre (0.40 ha) in size and weighing 250 tons, planted in 1894 of the Chinese lavender variety.

Wisteria species are used as food plants by the larvae of some Lepidoptera species including brown-tail.

Wisteria are produced in pendulous racemes 10 to 80 cm long, similar to those of the genus Laburnum, but are purple, violet, pink or white, but not yellow.Flowering is in the spring (just before or as the leaves open) in some Asian species, and in mid to late summer in the American species and W. japonica.

The flowers of some species are fragrant, most notably Chinese Wisteria. The seeds are produced in pods similar to those of Laburnum, and, like the seeds of that genus, are poisonous.

Wisteria is considered an invasive species in many parts of the US, especially the Southeast, due to its ability to overtake and choke out other native plant species.