Acropora horrida is a species of acroporid coral that was first described by James Dwight Dana in 1846. Found in tropical, shallow reefs in marine environments, it occurs near fringing reefs around turbid water, at depths of 5 to 20 m (16 to 66 ft). It is listed as a vulnerable species on the IUCN Red List, and it is thought to have a decreasing population. It is not common and found over a large area, and is listed under CITES Appendix II.

Description Acropora horrida forms in colonies, which are mainly open branched. It is light blue, dark blue, light yellow, or brown in colour, with white or pale blue polyps. The main branches contain an unorganised structure of branchlets, based on examples in water showing turbidity. However, in clear water, the branchlets are short, making the structure appear bristly. The corallites are rough and irregularly placed, and tentacles enlarge during the day. There are no similar species within genus Acropora. It is found in marine, tropical, shallow reefs, mainly in turbid water near fringing reefs.