Eric Segelberg (20 December 1920 Nykoping, Sweden – 17 October 2001 Uppsala, Sweden) was theologian and a priest of the Lutheran Church of Sweden.
Segelberg was ordained to priesthood in 1944, and he continued to study Theology and Classics at both Uppsala and Oxford Universities, getting doctor's degree in the History of Religion. His dissertation in 1958 was on the "Maşbūtā. Studies in the Ritual of the Mandæan Baptism". He became professor of Classics at Dalhousie University, Canada in 1968. As Emeritus he returned to Sweden. Widely known in many fields, he specialized in study of Patristics and the Mandeans and gnosticism. His main specialization was in liturgics. His quite outstanding liturgical knowledge was characterizing his studies in history of religion. Well-known are his studies "The Benedictio Olei in the Apostolic Tradition of Hippolytus", (Oriens Christianus 48, 1964), and "The Ordination of the Mandæan tarmida and its Relation to Jewish and Early Christian Ordination Rites", (Studia Patristica 10, 1970).
Segelberg was member of the Societas Sanctae Birgittae and in Sweden a well known member of the Swedish high church movement Arbetsgemenskapen Kyrklig Förnyelse ("The Church Union in Sweden"). He established a trust in 1984 to enhance Christian theological research, education and youth work. In Sweden he founded "Segelbergska stiftelsen för liturgivetenskaplig forskning" (The Segelberg foundation on liturgical research), sited in Uppsala, Sweden. In 1990 it was published a Festschrift to him, collecting a lot of his own writings: Gnostica – mandaica – liturgica. Opera eius ipsius selecta & collecta septuagenario Erico Segelberg oblata curantibus Jan Bergman, Jan Hjärpe, Per Ström una cum Bibliographia Segelbergiana ab Oloph Bexell redacta (Acta Universitatis Upsaliensis. Historia Religionum 11.).