Recognition Professor Okpewho's work has come with some of the most prestigious fellowships in the humanities: from the Woodrow Wilson International Center for Scholars (1982), Alexander von Humboldt Foundation (1982), Center for Advanced Study in the Behavioral Sciences at Stanford (1988), the W.E.B. Du Bois Institute at Harvard (1990), National Humanities Center in North Carolina (1997), and the Simon Guggenheim Memorial Foundation (2003). He was also elected Folklore Fellow International by the Finnish Academy of the Sciences in Helsinki (1993).

Administrative positions he has held include headship of the Department of English at the University of Ibadan and chairmanship of the Department of Africana Studies at Binghamton University. He belongs to several professional scholarly bodies such as the African Studies Association, African Literature Association, American Folklore Society, Modern Language Association, International Society for Oral Narrative Research, and International Society for Oral Literature in Africa, with official stints as member of the Board of Directors of the African Studies Association, member of the editorial committee of the series Teaching Languages, Literatures, and Cultures of the Modern Language Association, member of the editorial board of the journals Okike and Oral Tradition, editor of the Journal of African and Comparative Literature, and president of the International Society for Oral Literature in Africa.