赤桉（学名：Eucalyptus camaldulensis）为桃金娘科桉属下的一个种。

Eucalyptus camaldulensis, the river red gum, is a tree of the genus Eucalyptus. It is one of around 800 in the genus. It is a plantation species in many parts of the world, but is native to Australia, where it has the most widespread natural distribution of Eucalyptus in Australia, especially beside inland water courses. Oddly, it is named for a private estate garden near the Camaldoli monastery near Naples (L'Hortus Camaldulensis di Napoli), from where the first specimen came to be described. Material from this tree was used by Frederick Dehnhardt, Chief Gardener at the Botanic Gardens in Naples, to describe this species in 1832.