Judah David Bleich (born August 24, 1936, Tarrytown, New York) is an authority on Jewish law and ethics, including Jewish medical ethics. He is rabbi of Cong. B'nei Jehuda. He is a professor of Talmud (rosh yeshiva) at the Rabbi Isaac Elchanan Theological Seminary, an affiliate of Yeshiva University, as well as head of its postgraduate institute for the study of Talmudic jurisprudence and family law. At Yeshiva University, he holds the Herbert and Florence Tenzer Chair in Jewish Law and Ethics and also teaches at the Cardozo Law School. He is married to Dr. Judith Bleich, a historian of 19th-century European Jewry.
Bleich brings an Orthodox perspective to governmental deliberations on bioethics. For example, in 1988 he served on the NIH Human Fetal Tissue Transplantation Research Panel and testified before Congress on the Pain Relief Promotion Act. In 1984, New York's Mario Cuomo appointed Bleich to the Governor’s Commission on Life and the Law.
Bleich is the older of two sons of Rabbi Manning H. Bleich and his wife Beatrice. He attended public elementary school and received private tutoring on Jewish subjects. Later, he studied in Yeshiva Torah Vodaath and Beis Medrash Elyon, under Rabbi Elya Chazan. From 1958–1962 he attended the Kollel in Yeshiva Chofetz Chaim of Radun. He received a bachelor's degree from Brooklyn College in 1960, a master's degree from Columbia University in 1968, and a PhD from New York University in 1974.