Ahimaaz (Hebrew: אחימעץ ʾAḥimaʿats "My Brother Is Counselor") was son of the high priest Zadok.

He first appears in the reign of King David (reigned c. 1000-962 BCE). During Absalom's revolt he remained faithful to David, and assisted him by giving him news about the proceedings of Absalom in Jerusalem (2 Samuel 15:24-37; 17:15-21). He was a swift runner, and was the first to bring David news of the defeat of Absalom, although he refrained from mentioning his death (2 Samuel 18:19-33).

Under King Solomon (c. 970–930 BCE), Ahimaaz's father Zadok became high priest. When Zadok died, Ahimaaz succeeded him in that position (1 Chronicles 6:8, 53).

He may have been the same Ahimaaz who took as wife Basemath, one of Solomon's daughters (1 Kings 4:15). Subsequent kings of Israel, Ahaz, also married daughters of the high priest.