[[File:History of Rome and the Popes in the Middle Ages (1911) (14760946554).jpg|thumb|Epitaph of Eutychian; the bottom line reads "Eutychianos Epis[kopos]," 'Bishop Eutychian.']]
Pope Eutychian, also called Eutychianus (), was the bishop of Rome from 4 January 275 to his death on 7 December 283.
Eutychian's original epitaph was discovered in the catacomb of Callixtus (see Kraus, Roma sotterranea, p. 154 et seq.), but almost nothing more is known of him. Even the date of his reign is uncertain. Liber Pontificalis gives a reign of 8 years and 11 months, from 275 to 283. Eusebius, on the other hand says his reign was only 10 months.
Eutychian's feast day is 8 December.