Leslie Ryan was born in Penarth, South Wales. He was an organ scholar at Llandaff Cathedral, Cardiff. Leslie was head of music at Morriston Comprehensive School, Bishop Gore School where he was also head of the faculty of Creative Arts, and at Gorseinon College, Swansea where he specialised in teaching AS, A level and Scholarship level music.
Leslie is featured on nine of the Morriston Orpheus Choir recordings either as organist or musical director. Leslie is currently the organist for the Orpheus Choir.
He is organist and co-director of music with his wife Penny at All Saints Church Oystermouth, Swansea. In 2005 he was awarded the Archbishop of Wales Certificate of Merit in Church Music.
Leslie enjoys composing and arranging music, and has written several special arrangements for the Ariosa Singers. Many of his compositions and arrangements are published by Sibelius Music.