Bluefieldius is an extinct genus of marine ray-finned fish that lived during the Late Mississippian (Early Carboniferous) epoch in what is now West Virginia, United States. It is known from a single fossil collected from the late Serpukhovian or early Viséan Bluefield Formation. The type and only species (monotypy) is Bluefieldius mercerensis.
It has a "palaeoniscoid" body plan, although as that order is thought to be paraphyletic, it was described as an indeterminate actinopterygian.