The diocese Mangalore comprises of the civil districts of South Kanara and Udupi in Karnataka, and Kasargod in Kerala. Since the beginning of the sixteenth century Mangalore which formed a part of Kanara passed several times successively under the jurisdiction of Goa, Verapoly and Pondicherry.

On September 27, 1879 Kanara was entrusted by the Holy See to the care of the Jesuit Province of Venice.

With the official proclamation of the establishment of the Indian hierarchy in a Council of the Bishops of Southern India at Bangalore on January 25, 1887, Mangalore (including the present diocese of Calicut) took it's place in the Indian hierarchy as the diocese of Mangalore.

By an Apostolic Brief "Cum Auctus Fidelium Grex" on June 22, 1923 the diocese of Mangalore was divided by separating from it the district of Malabar which forms the present diocese of Calicut. With this division the restricted diocese of Mangalore was entrusted to it's own clergy. By a decree of the Sacred Congregation for Propaganda Fide dated January 12, 1960 the Hosdrug Taluk was detached from this diocese and was attached to the diocese of Calicut.

Name	Designation	Period
Most Rev. Basil S. D’Souza	Bishop	1965-1996
Most Rev. Raymond D’Mello	Bishop	1959-1964
Most Rev. Basil S. Peres	Bishop	1955-1958
Most Rev. Victor R. Fernandes	Bishop	1931-1955
Most Rev. Valerian J. D’Souza	Bishop	1928-1930
Most Rev. Paul Penni sj	Bishop	1910-1928
Most Rev. Abundius Cavadini sj	Bishop	1895-1910
Most Rev. Maria Pagani sj	Bishop	1887-1895
Most Rev. Nicholas Maria Pagani sj	Vicar Apostolic	1878-1886
Most Rev. Mary Epherm of Sacred Heart of Jesus ocd	Vicar Apostolic	1870-1873
Most Rev. Michael Antony of St. Louis ocd	Vicar Apostolic	1853-1870
Most Rev. Bernardine of St. Agnes ocd	Vicar Apostolic	1845-1853