Neoptolemus the Grammarian was a Hellenistic grammarian and literary critic from Parium, possibly Paros, who was active in the 2nd century BCE. His life is obscure and known only through later references, including one by the Roman poet Horace in the Ars Poetica. No works by Neoptolemus survive directly. He is credited with a systematic treatise on poetics, which Horace notes he compiled.

Later testimonia suggest his work may have organized poetics into a tripartite framework concerning the poem, the composition, and the poet. His writings survive only as fragments and references in later authors. Neoptolemus is significant for his influence on later literary theory. His theoretical framework, particularly this potential tripartite division, was a major source for Horace's Ars Poetica. Through this conduit, his ideas entered the mainstream of classical and European poetic theory, exemplifying the technical literary criticism of the Hellenistic period.