Vissarion (Bulgarian: Висарион) was a Patriarch of the Bulgarian Orthodox Church in the 13th century. He is the only Bulgarian Patriarch who was not included in the list of Patriarchs in the medieval Book of Boril. The only testimony of his existence is an undated seal reading "Vissarion, by the grace of God Patriarch of the Bulgarians". It is suggested that he presided over the Bulgarian Church during the rule of emperor Ivan Asen II (r. 1218–1241) and was omitted in the lists because he supported the union with the Catholic Church concluded by emperor Kaloyan (r. 1197–1207) and abolished by Ivan Asen II.