Rabbi Yishmael ben Elisha, the Kohen Gadol, was a Tanna and High Priest mentioned in the words of the Sages. According to the way rabbinic literature portrays him, he was among the leaders of the first generation of Tannaim and served as High Priest shortly before the destruction of the Second Temple.

The Talmud (Berachot 7a) records a baraita in his name in which he recounts entering the Holy of Holies to offer incense and seeing a divine vision there.

He should not be confused with the third-generation Tanna Rabbi Yishmael ben Elisha, colleague and halachic opponent of Rabbi Akiva and author of the baraita of the thirteen hermeneutical rules. One hypothesis holds that the latter was his grandson; some consider them one person, but this is hard to reconcile with the account of the High Priest's execution alongside Rabban Shimon ben Gamliel.

He is counted among the Ten Martyrs. According to tradition, he was executed together with Rabban Shimon ben Gamliel the Elder on 25 Sivan. The work Dorot HaRishonim disputes this tradition and suggests other identifications.

One source places his grave in the village of Sajur in the Galilee; a later source places it in Kfar Kanna.