Ctenochaetus tominiensis was first formally described in 1955 by the American ichthyologist John Ernest Randall with its type locality given as Sadaa Island in the Gulf of Tomini, Sulawesi, Indonesia.

[3] Ctenochaetus tominiensis has its dorsal fin supported by 8 spines and 24 or 25 soft rays while the anal fin is supported by 3 spines and 22 or 23 soft rays.

The rear ends of the dorsal and anal fins are, uniquely in the genus Ctenochaetus, angular.

[5] Ctenochaetus tominiensis is found in the western central Pacific Ocean from Malaysia and Indonesia east through East Timor, the Philippines, Palau, Micronesia, Papua New Guinea, the Solomon Islands, Tuvalu, Vanuatu and Fiji, south to the Great Barrier Reef.

[1] This species is found solitarily or in small aggregations on steep drop offs with dense coral growth in inshorse, sheltered waters at depths between 0 and 45 m (0 and 148 ft).