Antony of Siya (Russian: Антоний Сийский) (1479–1556) was a Russian Orthodox monk who was proclaimed a saint after his death. He founded the Antonievo-Siysky Monastery on the River Siya in modern Arkhangelsk Oblast, Russia.
Antony was born a peasant. He married while a young man and was a normal peasant until after the death of his wife. He then entered the monastery at Kargopol. He did not stay there long and afterward became a wandering monk along the shores of the Arctic Ocean.
Vasily's grandson Ivan wrote a biography on Antony.