Yoel Kahn, also spelled Kahan, is a senior Chabad rabbi, who served as the leading Choizer and Meiniach for the late Lubavitcher Rebbe, Rabbi Menachem Mendel Schneerson. He served in this role from the beginning of the Rebbe's leadership in 1950 until his death in 1994. Today he continues to serve as the senior Mashpia in the central Lubavitcher yeshiva at 770 Eastern Parkway. His position as leading Choizer and Meiniach makes him the default authority on the Rebbe's teachings specifically, and he is universally recognized as the greatest scholar of general Chabad Chassidic doctrine and thought. He is referred to familiarly amongst Chabad Chasidim as Reb Yoel. He is the son of Refoel Nachman (Folle) Kahn, author of Shemu'os VeSippurim. He has no children.

He was born in the Soviet Union, on 16 Shevat, 5690 which corresponds to February 14, 1930. His father Refoel Nachman Kahn, studied in the original Yeshiva Tomchei Temimim, in the town of Lubavitch, White Russia and authored Shemu'os VeSippurim an authoritative and multi-volume compilation of historical accounts and anecdotes, culled from the traditions handed down by reliable Chassidim of earlier generations and his own experiences. At a young age he emigrated to the Land of Israel together with his family, and studied in Yeshiva "Achai Temimim" in Tel Aviv under the tutelage of the famous Mashpia Rabbi Chaim Shaul Brook. During his teen years he also studied privately with the famed Mashpia and teacher of Chassidic thought Rabbi Moshe Gourarie. He also knew and was influenced by Rabbi Nochum Goldshmidt and to a lesser degree, by Rabbi Shlomo Chaim Kesselman.