Hywel David Lewis (21 May 1910 – 6 April 1992) was a Welsh theologian and philosopher.
Lewis was born in Llandudno, Wales and educated at Caernarfon grammar school, the University College of North Wales, Bangor (graduating with a first-class degree in philosophy in 1932) and Jesus College, Oxford (graduating with a BLitt in 1935). He was then a lecturer in philosophy at Bangor, becoming professor in 1947. In 1955, he was appointed Professor of the History and Philosophy of Religion at the University of London, retiring in 1977. His works included Morals and the New Theology (1947), Morals and Revelation (1951), Our Experience of God (1959), The Elusive Mind (1969), The Self and Immortality (1973), Persons and Life after Death (1978) and The Elusive Self (1982). He also published in Welsh. His interest in comparative religion led to his becoming founding editor of the journal Religious Studies, holding the post from 1964 to 1979. He edited the Muirhead Library of Philosophy from 1947 to 1978. He also served as president of the Aristotelian Society from 1962 to 1963 and as chairman of the council of the Royal Institute of Philosophy from 1965 to 1968. He died on 6 April 1992 and was buried at St Tudno's church on the Great Orme.