Thomas Joseph Riley (November 30, 1900 – August 17, 1977) was an American prelate of the Roman Catholic Church. He served as an auxiliary bishop of the Archdiocese of Boston from 1959 to 1976.
Thomas Riley was born in Waltham, Massachusetts, to Thomas and Agatha (née Loughry) Riley. Following his graduation from Boston College in 1922, he studied at St. John's Seminary in Brighton. He was ordained to the priesthood on May 20, 1927.
Riley served as a curate at St. Joseph's Church in Roxbury (1929–31) and earned a Doctor of Philosophy degree from the Catholic University of Louvain in 1933. He taught philosophy and moral theology at St. John's Seminary for eleven years, then serving as vice-rector (1944–51) and rector (1951–58) of the seminary. In 1958, he became pastor of St. Peter's Church in Cambridge.