The mandible (made from dermal bone) of this genus differs from Entelognathus and Qilinyu—two other maxillate placoderms from late Silurian China−in that the oral lamina is broad and carries a row of tooth-like denticles, though the marginal flange is toothless.

[1] The pectoral fin, preceded by two small spines on its thoracic shield, is lobate in shape and situated along by a 'fringe' of scales similar to those of Lepidotrichia in bony fishes.

[1] Bianchengichthys' mandible bears physical resemblance to both its relatives Qilinyu and Entelognathus as well as arthrodire placoderms.

[1] The Xiaoxi Formation primarily consists of sandstones, siltstones and mudstones, and ichnofossil assemblages from the vicinity of Guizhou suggest that it was deposited in a shallow, subtidal, marine setting.

[4] The presence of Cruziana in the Xiaoxi suggests that Bianchengichthys may have lived alongside burrowing organisms such as trilobites.