Saint Apollonius (d. c. 186) is a 2nd century Christian martyr and apologist who is not to be confused with Claudius Apollonius , an apologist of the same time frame.

In 180, Marcus Aurelius died. Aurelius had softened the perseuction of Christians during his reign. When Commodus came to the throne of Ancient Rome, he was a notoriously vicious ruler, but he relaxed the persecution of Christians further. Apollonius converted to Christianity some time around the last years of Aurelius, and some time around 186 one of Apollonius's slaves, a man named Severus, formally accused his master of being Christian (and therefore of denying the emporer cult of Rome). Severus himself was executed, under a law of Aurelius's that stipulated that anyone accusing another of being a Christian must himself be put to death. However, Christianity was still illegal, and Apollonius was arrested. Commondus referred his case to the Senate of Rome for settlement, and Apollonius composed an eloquent apology for the senators, saying,

". . . if it were a delusion (as you assert) which tells us that the soul is immortal, and that there is a judgment after death and a reward of virtue at the resurrection, and that God is the Judge, we would gladly be carried away by such a lie as that, which has taught us to lead good lives awaiting the hope of the future even while suffering adversities."

The apology made no difference in the end, however, and Apollonius was beheaded around the year 186.

His feast day in the Roman Catholic Church is April 18.