Phebronia of Nisibis, also known as Phebronia of Sebapte, was a nun at Nisibis, Roman Empire. She suffered persecution under Diocletian, who offered her freedom if she renounced her faith and married his nephew, Lysimachus, who had been leaning towards conversion to Christianity. Febronia refused and was tortured, suffered mutilation and death. Lysimachus, witnessing her suffering, converted.