John of Debar (; fl. 1018-1037) was an 11th-century Bulgarian clergyman. He was a bishop under Samuel of Bulgaria. According to Srđan Pirivatrić he became the last Bulgarian patriarch David in 1016. He remained in office, becoming the first Slavic Archbishop of Ohrid, after the fall of the First Bulgarian Empire to Byzantium. According to 17th-century French historian du Cange John was born in a village around the town of Debar in present-day North Macedonia. When in 1018 Emperor Basil II managed to conquer Bulgaria, he decided to abolish the previously autocephalic Bulgarian Orthodox Church, establishing the Archbishopric of Ohrid, which was in effect downgrading of the Bulgarian Patriarchate and corresponded to the newly formed Theme Bulgaria, which covered the western part of Bulgaria. John was chosen to be the first Archbishop of Ochrid. Prior to this he had been hegumen in a Debar monastery. He remained head of the Archbishopric until his death in 1037.