Tryphon of Constantinople was a 10th-century monk who served as the Ecumenical Patriarch of Constantinople. Following the death of Stephen II in 928, the Byzantine Emperor Romanos I Lekapenos appointed him to the position. This appointment included a specific agreement that Tryphon would resign once the Emperor's son, Theophylact, reached adulthood. Although he initially agreed to this arrangement, Tryphon later refused to step down, citing his belief that a minor should not hold the patriarchal throne.