A celebration of this event was held at the St. Ignatius church in Tokyo, a church which was dedicated by Doi in 1949. He attended the Second Vatican Council from 1962 to 1965, and was later one of the cardinal electors who participated in the 1963 papal conclave that selected Pope Paul VI.
Pope John XXIII created him Cardinal Priest of S. Antonio da Padova in Via Merulana in the consistory of 28 March 1960. Doi, hoped by the Vatican to enliven the Church in Japan, thus became the first Japanese member of the College of Cardinals.