Mary Dillon (born 1964), is an Irish folk singer, known for her work with the traditional band Déanta. She launched her solo career in 2010 with the release of an EP entitled Army Dreamers. She is the sister of singer Cara Dillon.
Mary Dillon was born in Dungiven, where she still lives with her two children, a son and a daughter. She was raised in a musical household and one of her five siblings is fellow folk singer Cara Dillon. She has never pursued singing as a full-time career and currently works as an English teacher at St Cecilia's College in Derry.