Nausiphanes (Greek: Ναυσιφάνης; lived c. 325 BC) was an ancient Greek atomist philosopher from Teos.

Nausiphanes reportedly had a large number of pupils, and was particularly famous as a rhetorician. He argued that the study of natural philosophy (physics) was the best foundation for studying rhetoric or politics, which is attacked in a surviving work of Philodemus, On Rhetoric. Furthermore, Nausiphanes was an adherent of Democritus's sceptical side and deemed human judgment as being no more than a realignment of atoms in the mind. Nausiphanes substituted the term akataplêxia (“undauntability”) for Democritus’ athambiê, “fearlessness,” as crucial for eudaimonia. Diogenes Laërtius recounts that Epicurus was at one time one of his students, but was unsatisfied with him, and apparently abused him in his writings. Epicurus may also have derived his Canon from the Tripod of Nausiphanes. Only the following summary of the Tripod by Philodemus survives: