Marcus Pacuvius (ca. 29 April 220 BC – 7 February 130 BC) was the greatest of the tragic poets of ancient Rome prior to Lucius Accius.

He was the nephew and pupil of Ennius, by whom Roman tragedy was first raised to a position of influence and dignity. In the interval between the death of Ennius (169 BC) and the advent of Accius, the youngest and most productive of the tragic poets, Pacuvius alone maintained the continuity of the serious drama, and perpetuated the character first imparted to it by Ennius. Like Ennius he probably belonged to an Oscan stock, and was born at Brundisium, which had become a Roman colony in 244 BC. Hence he never attained to that perfect idiomatic purity of style, which was the special glory of the early writers of comedy, Naevius and Plautus.

Pacuvius obtained distinction also as a painter; and Pliny the Elder (Nat. Hist. xxxv) mentions a work of his in the Temple of Hercules in the Forum Boarium. He was less productive as a poet than either Ennius or Accius; and we hear of only about twelve of his plays, founded on Greek subjects (among them the Antiope, Teucer, Armorum Judicium, Dulorestes, Chryses, Niptra, &c., most of them on subjects connected with the Trojan cycle), and one praetexta (Paulus) written in connexion with the victory of Lucius Aemilius Paullus Macedonicus at the Battle of Pydna (168 BC), as the Clastidium of Naevius and the Ambracia of Ennius were written in commemoration of great military successes.