Alcimus (Αλκιμος, Alkimos). A high priest for three years (ca. 161–159 bc), whose career is described in 1 Macc 7:4–50 and 9:1–57 (see also 2 Macc 14; Josephus, Antiquities 12.9–11; 20.10).

Alcimus was a descendant of Aaron, but not in the line of high priests (1 Macc 7:14; Josephus, Antiquities 20.10). However, he desired to become high priest and got the help of Demetrius, who had just overthrown Antiochus Eupator and made himself king. Demetrius sent an army from Antioch under Bacchides to establish Alcimus in the high priesthood at Jerusalem.

According to the Maccabean account, Alcimus was of the Hellenizing party of Jews, and therefore opposed by the Maccabees. Thus, when Bacchides left Jerusalem for Antioch, Simon Maccabeus attacked Alcimus, and he retreated to Syria. Demetrius then sent another army, led by Nicanor. Nicanor attacked Simon, but was killed. Bacchides himself then led a third army to save Alcimus. This time, Simon was killed and Alcimus was reestablished in Jerusalem as high priest. He died shortly afterward, possibly of a stroke (1 Macc 9:55–57).