Marcella María Althaus-Reid (May 11, 1952 – February 20, 2009) was an Argentine theologian and writer, Professor of Contextual Theology and Senior Lecturer in Systematic Theology and Christian Ethics at the School of Theology of New College, University of Edinburgh, Scotland. When she took office, she was the only female professor of theology at a Scottish university and the first female professor of theology at New College in its 160-year history. She participated in the feminist and LGBT liberation movements.