Pope Paul VI created him cardinal-priest of San Luca a Via Prenestina in the consistory of 28 April 1969. From 1969 to 1979, Poma served as president of the Italian Episcopal Conference; during this capacity, he warned that Catholics who support communism separate themselves from the Church. He was also one of the cardinal electors who participated in the conclaves of August and October 1978, which selected Popes John Paul I and John Paul II respectively. On 11 February 1983, the Cardinal resigned as Bologna's archbishop, after almost fourteen years of service. He continued to govern the archdiocese as its apostolic administrator until the appointment of Bishop Enrico Manfredini on the following 18 March.