Rav Kahana (III) (Hebrew: רב כהנא מפום נהרא, read as Rav Kahana Me-Pum-Nahara, lit. "Rabbi Kahana of Pum-Nahara"; Recorded in the Talmud merely as R. Kahana ) Was a Jewish Amora sage of Babylon, of the third and fourth generation of the Amora sages, and headed the Yeshiva of Pum-Nahara.
During his youth he studied under Judah ben Ezekiel, and after his death, he served at Rabbah bar Nahmani as well, and learned under him the tractate Sanhedrin along with his great friend R. Safra. He made Aliyah to the Land of Israel along with fellow R. Safra, and studied under R. Zeira, and under R. Abbahu. He also studied under Rabbi Hiyya b. Abba, who also prayed for his longevity, and indeed his blessing materialized.
After a while he returned to Babylonia, then had determined his residence at Pum-Nahara, where he studied with Rav Ashi, who became his disciple par excellence. The latter honored him much, however, Rav Ashi himself considered the Amemar as his principal Rabbi as well, and would trun to the Amemar in an honorary language of 'Mar' ("Sir"), an attitude that was not adopted by him, when he was speaking to Rav Kahana III as well.
He was a colleague of Rav Nachman bar Yitzchak, and together they rebuked the "haughty of spirit" (The rich, who intervene in appointees of the Dayans, religious Judges, and those of the community leaders), "Whom in their lifted up hearts and their great wealth shall forget their duties".
He was a Kohen ("priest"), from Eli ha-Kohen's family.
Kahana's Yeshiva in Pum-Nahara was subordinated to the Yeshiva in Sura, but from the times of Rava's death and onward, the heads of the Yeshiva in Nehardea would frequently visit Rav Kahana III in Pum-Nahara, most likely for the purpose of reinforcing their Yeshiva's influence over the Yeshiva in Pum-Nahara. This reinforcement of ties, between Nehardea and Pum-Nahara, is attested by the fact that Kahana III gave his funeral oration to Rav Zevid of Nehardea at Pum-Nahara.