Gymnothorax bacalladoi is a moderately elongate moray with the dorsal fin origin before the gill openings, four infraorbital pores and one branchial pore. The outer teeth are serrate, the maxillary teeth are in two short rows, and the vomerine teeth are biserial.
Coloration is mottled brown, with posterior jaw pores in white spots.
There are only three known specimens all of which have been collected from rocky bottoms. Gymnothorax bacalladoi may inhabit deeper waters.