Bertoli studied in Lucca, then at the Pontifical Roman Seminary in Rome. After graduation he received on August 15, 1930 in Lucca, the sacrament of Holy Orders. In 1933 he became the first speaker, then secretary of the Apostolic Nunciature in Belgrade Nuncio Ermenegildo Pellegrinetti. During the Second World War he served first in the Nunciature in Paris, then in 1942 in Haiti. In 1946 he moved to Bern in Switzerland, where he participated in numerous international conferences to study the problems of war refugees. In 1948 he also participated in the International Conference of the Red Cross in Stockholm and represented the Holy See at the Conference on the Revision of the Geneva Conventions. In the spring of 1949, he should go to the Nunciature in Prague, but this failed due to opposition of the Czechoslovak government.
On March 24, 1952, he was named by Pope Pius XII. Titular Archbishop of Nicomedia and apostolic delegate to Turkey. He received his episcopal consecration Cardinal Eugène Tisserant on 11 May of the same year; Co-consecrators were Archbishop Curia Valerio Valeri and Archbishop Filippo Bernardini. Just one year later, on May 7, 1953, he was appointed Apostolic Nuncio to Colombia, then appointed in France on April 15, 1959 in Lebanon, and on 16 April 1960. From 1962 to 1965 he took part in the Second Vatican Council.
By Pope Paul VI. taken as a cardinal deacon with the title Diakonia San Girolamo della Carita in the College of Cardinals in the consistory of April 28, 1969, he was appointed on May 7, 1969 Cardinal Prefect of the same rearranged Congregation for the Causes of Saints, which he to March 1 1973 remained. On March 5, 1973, he was elevated to Cardinal Priest of the titular church of San Girolamo dei Croati. In 1976 he was called by Pope Paul VI. while the local bloody crisis again sent to Lebanon.
In August 1978, he took part in the conclave that elected John Paul I, finally emerged two months later on October Conclave 1978, from the Pope John Paul II. From January 27 to February 13, 1979 Cardinal Bertoli took part in the third General Conference of Latin American Bishops in Puebla. John Paul II finally appointed him on May 5, 1979 Cardinal Chamberlain of the Catholic Church, which finally on June 30, 1979 drew an elevation to cardinal bishop of Frascati by itself. As such, it was on December 24 at the opening of the extraordinary Holy Year and papal legate for the opening of the Holy Door of the Papal Basilica of St Paul Outside the Walls. He remained Camerlengo until 25 March 1985.
On 8 November 2001 Paolo Bertoli died at the age of 93 years.