Balagrus the Historian was a Greek author of the 2nd century CE during the Roman period. No details of his life, origins, or education survive. His sole known work is a historical text, now lost and known only through a single fragment.

This fragment, concerning the consumption of a specific fish, is preserved by Athenaeus of Naucratis in his Deipnosophistae, or The Learned Banqueters. Balagrus is a minor figure whose significance derives entirely from his citation in Athenaeus’s compendium, which salvages fragments from many lost authors. The passage provides a minor datum for ancient dietary habits.