Samuel ben Nahman (Hebrew: שמואל בן נחמן) or Samuel [bar] Nahmani (Hebrew: שמואל [בר] נחמני) was a rabbi of the Talmud, known as an amora, who lived in the Land of Israel from the beginning of the 3rd century until the beginning of the 4th century. He was a pupil of R. Jonathan ben Eleazar (Pes. 24a) and one of the most famous haggadists of his time (Yer. Ber. 12d; Midr. Teh. to Ps. ix. 2). He was a native of the Land of Israel and may have known the patriarch Judah I (Gen R. ix.). It appears that he went to Babylon in his youth but soon returned to Israel (Sanh. 96b).
Samuel ben Nahman seems to have gone to Babylon a second time in an official capacity in order to determine the intercalation of the year, which, for political reasons, could not be done in Israel (Yer. Ber. 2d; Pes. 54b). As an old man he went to the court of Empress Zenobia (267-273) to petition her to pardon an orphaned youth who had committed a grave political crime (Yer. Ter. 46b). In the days of Judah II, Samuel ben NaḤman appears among the most intimate associates of the patriarch, with whom he went (286) to Tiberias at Diocletian's order; later he joined the emperor at Paneas (Yer. Ter. ix., end; Gen. R. lxiii.).