Joachim I may refer to:
Joachim I, Primate of Bulgaria in 1232–1246 Patriarch Joachim I of Constantinople (r. 1498–1502 and 1504) Joachim I Nestor, Elector of Brandenburg (1484–1535) Patriarch Joachim of Alexandria (r. 1486–1567) Patriarch Joachim of Moscow and All Russia (1620–1690) Joachim I of Naples (1767–1815)