Allocasuarina littoralis, commonly known as black she-oak,[3] is a species of flowering plant in the family Casuarinaceae and is endemic to eastern Australia.

Allocasuarina littoralis is a dioecious, or less commonly a monoecious tree or shrub, that typically grows to a height of 5–15 m (16–49 ft).

[3][4][5] Black she-oak was first formally described in 1796 by Richard Anthony Salisbury, who gave it the name Casuarina littoralis in his Prodromus stirpium in horto ad Chapel Allerton vigentium from specimens collected at Botany Bay by Joseph Banks.

[6][7] It was reclassified in 1982 as Allocasuarina littoralis by Lawrie Johnson in the Journal of the Adelaide Botanic Gardens.

[9] Allocasuarina littoralis mainly grows on sand in woodland in near-coastal areas and on nearby tablelands, sometimes in heavy clay or among rocks, and occasionally in tall heath.