The Blastomussa merleti coexists in the Indo-Pacific region with other species in the same genus, B. wellsi and B.

[5] Its range extends from the Red Sea and the coast of East Africa, through the Indian Ocean, to northern and western Australia, Japan, the East China Sea and the islands of the oceanic West Pacific.

It inhabits a range of reef habitats, including steep slopes and crevices, at depths down to about 50 metres (160 ft).

The population trend is unknown but it is probable that the number of mature colonies is decreasing as a result of destruction of its reef habitats.

As well as collecting food particles with their tentacles and obtaining energy from their symbiotic zooxanthellae, the polyps can extract organic carbon from the water.