The Casuarinaceae are a family of dicotyledonous flowering plants placed in the order Fagales, consisting of four genera and 91 species[2] of trees and shrubs native to eastern Africa, Australia, Southeast Asia, Malesia, Papuasia, and the Pacific Islands.

Members of this family are characterized by drooping equisetoid (meaning "looking like Equisetum"; that is, horsetail) twigs, evergreen foliage, monoecious or dioecious and infructescences ('fruiting bodies') strobiloid or cone-like, meaning combining many outward-pointing valves, each containing a seed, into roughly spherical, cone-like, woody structures.

[7] In Australia, the most widely used common name for Casuarinaceae species is sheoak or she-oak (a comparison of the timber quality with English oak).

Other common names in Australia include ironwood, bull-oak or buloke, beefwood,[8] or cassowary tree.

Modern molecular phylogenetics suggest the following relationships:[10] Myricaceae (outgroup) Gymnostoma Ceuthostoma Allocasuarina Casuarina