Buchanania is a genus of plants in the mango and cashew family Anacardiaceae, native to areas from India to southern China, and southwards to northern Australia and the western Pacific.

This genus consists of trees with simple, unlobed leaves arranged alternately on the twigs. Flowers are produced in axillary or terminal panicles. Flowers are bisexual, i.e. they have both male and female organs. They usually have 5 calyx lobes and 5 petals, sometimes 4 or 6, and are pale green to white. There are 10 stamens and 4–6 carpels, only one of which is fertile. Fruits are more or less lens-shaped drupes with a bony or woody endocarp, and contain a single seed. Unlike other genera in the family, Buchanania does not appear to cause contact dermatitis.

The genus Buchanania was erected in 1801 by German botanist Kurt Polycarp Joachim Sprengel based on a collection of plant material by Francis Buchanan-Hamilton from what is now Myanmar. The genus was named after the collector.

The genus is native to areas from South and Southeast Asia, extending to northern Australia and the western Pacific. The full distribution is as follows:

As of 21 April 2024^[update], Plants of the World Online recognises 26 species in the genus, as follows:

The following names were previously recognised as species of Buchanania.