R. Ahai (, read as Rav Achai; sometimes recorded as R. Aha, Hebrew: רב אחא, read as Rav Acha) was a Jewish Savora sage of the first generation of the Savora era. R. Ahai is the most recorded Savora sage in the Babylonian Talmud. His thorough questions in the Talmud are excerpted as a foreword: "R. Ahai retorted:...". The sages of the Land of Israel said of him:
As to his exact identification and period, there are number of premises.