Carlo Confalonieri (Seveso, 25 July, 1893 – 1986, 1 August, Rome) was an Italian cardinal of the Roman Catholic Church.

Confalonieri travelled with Ratti to Rome as his attendant, or conclavist, for the 1922 papal conclave, at which the Cardinal was elected to the papacy as Pius XI.

He continued to serve as Ratti's secretary until the Pope's death in 1939, and during that period he was raised to the rank of Monsignor (7 February 1922), Protonotary Apostolic (24 December 1935), and canon of St. Peter's Basilica (1935).

Confalonieri was intended to be appointed Substitute, or Deputy, Secretary of State in 1937, but the position instead went to Giovanni Battista Montini.

He received his episcopal consecration on the following 4 May from Pius XII himself, with Archbishop Giuseppe Migone and Bishop Alfonso de Romanis, OSA, in the Sistine Chapel.

Confalonieri became Secretary of the Sacred Congregation for Seminaries and Universities on 25 January 1950, and later Titular Archbishop of Nicopolis ad Nestum on 22 February of that same year.

Pope John XXIII created him Cardinal-Priest of S. Agnese fuori le mura in the consistory of 15 December 1958, and Confalonieri was later appointed Archpriest of the Liberian Basilica on 16 November 1959.

His funeral Mass was held in Saint Peter's Basilica three days later, on 4 August, and was presided by Pope John Paul II.