Uwain may refer to:

• Abd Al Aziz Sayer Uwain Al Shammeri (born 1973), one of the Kuwaiti detainees at Guantanamo Bay
• Sir Uwain, a Knight of the Round Table in Arthurian legend

• Roman Cappadocia
• Roman Capriccio: The Pantheon and Other Monuments
• Roman Carnival
• Roman cartographers
• Roman-cassie
• Roman castra in Romania
• Roman Castulin
• Roman Catholic Apostolic Vicariate of Bontoc-Lagawe
• Roman Catholic Apostolic Vicariate of Calapan
• Roman Catholic Apostolic Vicariate of El Beni
• Roman Catholic Apostolic Vicariate of Izabal
• Roman Catholic Apostolic Vicariate of Puerto Princesa
• Roman Catholic Archbishop of Abidjan
• Roman Catholic Archbishop of Abuja
• Roman Catholic Archbishop of Acapulco
• Roman Catholic Archbishop of Accra
• Roman Catholic Archbishop of Acerenza
• Roman Catholic Archbishop of Adelaide
• Roman Catholic Archbishop of Agana
• Roman Catholic Archbishop of Agaña
• Roman Catholic Archbishop of Agra
• Roman Catholic Archbishop of Agrigento
• Roman Catholic Archbishop of Aix
• Roman Catholic Archbishop of Alba Iulia
• Roman Catholic Archbishop of Albi