Zosimus, Zosimos, Zosima or Zosimas may refer to:
- Rufus and Zosimus (died 107), Christian saints
- Zosimus (martyr) (died 110), Christian martyr who was executed in Umbria, Italy
- Zosimos of Panopolis, also known as Zosimus Alchemista, 3rd-century alchemist
- Zosimus the Hermit, 3rd-century Christian ascetic
- Zosimus, bishop of Naples, c. 356 – c. 362
- Zosimas of Palestine (c. 460 – c. 560), Eastern Orthodox saint
- Zosimus (historian) (c. 490–510) 5th-century Byzantine historian
- Pope Zosimus (died 418), born in Mesoraca, Calabria, who reigned from 417 to his death in 418
- Zosimos of Samosata, mosaicist at Zeugma
- Zosimus, 5th-century hermit who discovered Mary of Egypt in the desert
- Zosimus the Epigrammist in Anthologia Graeca
- John Zosimus (Ioane-Zosime), 10th-century Georgian monk and hymnist
- Zosimas of Solovki (died 1478), Russian Orthodox saint, founder of Solovetsky Monastery
- Zosimus, Metropolitan of Moscow (died 1494), Metropolitan of Moscow and Russia from 1490, author of the Third Rome conception
- Zosima, character in the 1880 novel The Brothers Karamazov by Fyodor Dostoyevsky