As a seminarian at the Almo Collegio Capranica Luigi Traglia studied in Rome, the subjects philosophy and Catholic theology. He received on August 10, 1917 Cardinal Vicar Basilio Pompilj the sacrament of Holy Orders, and then worked as a lecturer at the Pontifical Athenaeum " De Propaganda Fide ". In addition, he worked from 1927 to the Curia, where his focus was in the area of seminaries and Catholic universities. In 1930 he was assessor of the CDF. On February 22, 1932, he was by Pope Pius XI. the title Prelate of His house lent holiness, and from 17 September 1936, he worked as an auditor for the Roman Rota.
Pope Pius XI. appointed him Titular Archbishop of Cesarea in 1936 in Palestine and auxiliary bishop for the diocese of Rome. The bishop ordained Luigi Traglia by Cardinal Francesco Marchetti Selvaggiani, the Cardinal Vicar of Rome. Pope Pius XII. appointed Luigi Traglia President of the Special Commission for the Marian Jubilee Year 1953. 1959 he served as President of the Commission for the Roman synod.
Pope John XXIII. took him on 28 March 1960 as a cardinal priest with the titular church of Sant'Andrea della Valle in the College of Cardinals. Luigi Traglia took in the years 1962-1965 at the Second Vatican Council, in part, was from 1965 to 1968 Cardinal Vicar of the Pope for the diocese of Rome and in 1968 Chancellor of the Holy Roman Church. In 1969 he moved his Cardinal title to that of the titular church of San Lorenzo in Damaso. He was elevated to cardinal bishop of Albano in 1972. In 1973 he resigned his office as Chancellor of the Holy Roman Church, which was then vacant again. He was elected in 1974 to the Cardinal Dean and bestowed on him the title of cardinal associated Bishop of Ostia.
He died on 22 November 1977 in Rome and was initially buried in the local cemetery " Campo Verano ". In 1982 his remains were transferred to the Roman basilica of San Lorenzo in Damaso.
- 1954: Grand Officer of the Order of Merit of the Italian Republic
- 1963: Grand Cross of the Order of Merit of the Italian Republic
Membership in the Order of Malta
- Honour and Devotion - Bailli