This species forms the largest colonies of all Acropora (commonly 4 metres across, 2 metres high, with bases 0.4 metres thick) with parallel, obliquely inclined, very thick tapered branches. Branches are horizontally flattened towards their extremities. Corallites are tubular and irregular in length. Axial corallites, if formed at all, are indistinct.
Tan or pale brown with white axial corallites.
Shallow outer reef slopes exposed to wave action.