Mary Cecilia Grey is an English Catholic ecofeminist liberation theologian in the United Kingdom. She edited the journal Ecotheology for 10 years. She has previously been a professor teaching pastoral theology at the University of Wales, Lampeter; contemporary theology at the University of Southampton, La Sainte Union, and St Mary's University, Twickenham; and feminism and Christianity at the Catholic University of Nijmegen in the Netherlands.