| Date | Age | Event | Bishop | Title | Current Title |
| May | 55.2 | Appointed | Omar de Jesús Mejía Giraldo | Apostolic Administrator of San Vicente del Caguán, Colombia | Archbishop of Florencia, Colombia |
| 1 May | 89.5 | Died | Geraldo Dantas de Andrade, S.C.I. † | Auxiliary Bishop Emeritus of São Luís do Maranhão, Brazil |
| 64.5 | Died | José Daniel Falla Robles † | Bishop of Soacha, Colombia |
| 2 May | 46.6 | Ordained Bishop | Benoni Ambăruş | Titular Bishop of Truentum | Archbishop of Matera-Irsina, Italy |
| 86.5 | Died | Paul Vollmar, S. M. † | Auxiliary Bishop Emeritus of Chur, Switzerland |
| 3 May | 82.9 | Appointed | Angelo Amato, S.D.B. † | Cardinal-Priest of Santa Maria in Aquiro | Cardinal, Prefect Emeritus of the Congregation for the Causes of Saints |
| 92.3 | Appointed | Walter Brandmüller | Cardinal-Priest of San Giuliano dei Fiamminghi | Cardinal, President Emeritus of the Pontifical Committee for Historical Sciences |
| 72.8 | Appointed | Raymond Leo Burke | Cardinal-Priest of Sant’Agata de’ Goti | Cardinal, Patron Emeritus of Sovereign Military Hospitaller Order of Saint John of Jerusalem, of Rhodes and of Malta |
| 48.9 | Appointed | Matthew Remijio Adam Gbitiku, M.C.C.I. | Apostolic Administrator of Rumbek, South Sudan | Bishop of Wau, South Sudan |
| 71.1 | Appointed | Kurt Koch | Cardinal-Priest of Nostra Signora del Sacro Cuore | Cardinal, Prefect of the Dicastery for Promoting Christian Unity |
| 86.9 | Appointed | Francesco Monterisi | Cardinal-Priest of San Paolo alla Regola | Cardinal, Archpriest Emeritus of the Basilica di San Paolo fuori le Mura {Saint Paul Outside-the-Walls Basilica} |
| 76.6 | Appointed | Mauro Piacenza | Cardinal-Priest of San Paolo alle Tre Fontane | Cardinal, Major Penitentiary Emeritus of the Apostolic Penitentiary |
| 78.5 | Appointed | Gianfranco Ravasi | Cardinal-Priest of San Giorgio in Velabro | Cardinal, President Emeritus of the Pontifical Commission for Sacred Archeology |
| 75.8 | Appointed | Robert Sarah | Cardinal-Priest of San Giovanni Bosco in via Tuscolana | Cardinal, Prefect Emeritus of the Congregation for Divine Worship and the Discipline of the Sacraments |
| 88.8 | Died | Iñaki Mallona Txertudi, C.P. † | Bishop Emeritus of Arecibo, Puerto Rico |
| 4 May | 75.7 | Died | Antony Anandarayar † | Archbishop Emeritus of Pondicherry and Cuddalore, India |
| 87.3 | Died | Aloísio Hilário de Pinho, F.D.P. † | Bishop Emeritus of Jataí, Goias, Brazil |
| 90.6 | Died | Peter Toshio Jinushi † | Bishop Emeritus of Sapporo, Japan |
| 90.0 | Died | Raúl Horacio Scarrone Carrero † | Bishop Emeritus of Florida, Uruguay |
| 5 May | 55.3 | Appointed | Alessandro Cassinis Righini | Auditor General of the Office of the Auditor General |
| 73.2 | Resigned | Gino Reali | Bishop of Porto-Santa Rufina, Italy | Bishop Emeritus |
| 58.2 | Appointed | Gianrico Ruzza | Apostolic Administrator of Porto-Santa Rufina, Italy | Bishop of Civitavecchia-Tarquinia, Italy |
| 6 May | 65.1 | Died | Basil Bhuriya, S.V.D. † | Bishop of Jhabua, India |
| 96.3 | Died | Georges Marcel Émile Nicolas Perron, O.F.M. Cap. † | Bishop Emeritus of Djibouti |
| 56.9 | Ordained Bishop | Pascual Benjamín Rivera Montoya, T.O.R. | Prelate of Huamachuco, Peru |
| 7 May | 75.0 | Retired | William (Leonard) Kenney, C.P. | Auxiliary Bishop of Birmingham, England, Great Britain | Auxiliary Bishop Emeritus |
| 66.2 | Appointed | Giuseppe Mazzafaro | Bishop of Cerreto Sannita-Telese-Sant’Agata de’ Goti, Italy |
| 8 May | 47.6 | Appointed | Peter Adrian Chifukwa | Bishop of Dedza, Malawi |
| 66.7 | Appointed | Aldo Giordano † | Apostolic Nuncio to European Union |
| 58.4 | Appointed | Giuseppe La Placa | Bishop of Ragusa, Italy |
| 11 May | 52.4 | Appointed | François-Xavier Bustillo, O.F.M. Conv. | Cardinal, Bishop of Ajaccio, France |
| 63.0 | Appointed | Joseba Segura Etxezarraga | Bishop of Bilbao, Spain |
| 12 May | 55.4 | Appointed | Shorot Francis Gomes | Bishop of Sylhet, Bangladesh |
| 52.3 | Appointed | Wiesław Andrzej Śmigiel | Apostolic Administrator of Bydgoszcz, Poland | Archbishop of Szczecin-Kamień, Poland |
| 72.5 | Resigned | Jan Karol Tyrawa | Bishop of Bydgoszcz, Poland | Bishop Emeritus |
| 13 May | 52.0 | Ordained Bishop | Maurizio Aloise | Archbishop of Rossano-Cariati, Italy |
| 57.8 | Ordained Bishop | Gérard Francis Le Stang | Bishop of Amiens, France |
| 51.5 | Appointed | David Thomas Daniel Macaire, O.P. | Apostolic Administrator of Basse-Terre (et Pointe-à-Pitre), Guadeloupe, Antilles | Archbishop of Fort-de-France (e Saint Pierre), Martinique, Antilles |
| 50.4 | Appointed | Siby Mathew Peedikayil, H.G.N. | Bishop of Aitape, Papua New Guinea |
| 75.2 | Retired | Jean-Yves Riocreux | Bishop of Basse-Terre (et Pointe-à-Pitre), Guadeloupe, Antilles | Bishop Emeritus |
| 59.1 | Appointed | Luis José Rueda Aparicio | Apostolic Administrator of Soacha, Colombia | Cardinal, Archbishop of Bogotá, Colombia |
| 14 May | 67.6 | Appointed | Martin Ashe | Auxiliary Bishop of Melbourne, Australia |
| 67.6 | Appointed | Martin Ashe | Titular Bishop of Muteci | Auxiliary Bishop of Melbourne, Australia |
| 64.0 | Appointed | Anthony John Ireland | Auxiliary Bishop of Melbourne, Australia | Archbishop of Hobart, Australia |
| 64.0 | Appointed | Anthony John Ireland | Titular Bishop of Carinola | Archbishop of Hobart, Australia |
| 15 May | 55.5 | Appointed | Miguel Ángel Cadenas Cardo, O.S.A. | Vicar Apostolic of Iquitos, Peru |
| 59.8 | Appointed | Ramón Alfredo de la Cruz Baldera | Bishop of San Francisco de Macorís, Dominican Republic |
| 58.0 | Ordained Bishop | Teodoro Gómez Rivera | Titular Bishop of Castellum Tatroportus | Bishop of Choluteca, Honduras |
| 79.4 | Retired | Fausto Ramón Mejía Vallejo | Bishop of San Francisco de Macorís, Dominican Republic | Bishop Emeritus |
| 60.1 | Ordained Bishop | Marcos Pirán Gómez | Titular Bishop of Boseta | Auxiliary Bishop of Holguín, Cuba |
| 16 May | 59.6 | Ordained Bishop | Marc Michel Beaumont | Bishop of Moulins, France |
| 17 May | 63.9 | Resigned | Joseph Banga Bane | Bishop of Buta, Congo (Dem. Rep.) | Bishop Emeritus |
| 61.7 | Appointed | Stephen Chow Sau-yan, S.J. | Cardinal, Bishop of Hong Kong [Xianggang], China |
| 93.4 | Died | Bruno Kouamé † | Bishop Emeritus of Abengourou, Côte d’Ivoire |
| 56.1 | Appointed | Jean-Bertin Nadonye Ndongo, O.F.M. Cap. | Apostolic Administrator of Buta, Congo (Dem. Rep.) | Bishop of Lolo, Congo (Dem. Rep.) |
| 18 May | 67.9 | Appointed | Italo Dell’Oro, C.R.S. | Auxiliary Bishop of Galveston-Houston, Texas, USA |
| 67.9 | Appointed | Italo Dell’Oro, C.R.S. | Titular Bishop of Sucarda | Auxiliary Bishop of Galveston-Houston, Texas, USA |
| 19 May | 53.4 | Ordained Bishop | Roberto Madrigal Gallegos | Bishop of Tuxpan, Veracruz, México |
| 75.5 | Retired | Salvatore Paruzzo | Bishop of Ourinhos, Sao Paulo, Brazil | Bishop Emeritus |
| 56.1 | Appointed | Eduardo Vieira dos Santos | Bishop of Ourinhos, Sao Paulo, Brazil |
| 20 May | 66.2 | Ordained Bishop | Daniel John Felton | Bishop of Duluth, Minnesota, USA |
| 21 May | 78.0 | Retired | Isidro Barrio Barrio | Bishop of Huancavélica, Peru | Bishop Emeritus |
| 51.2 | Appointed | Luis Alberto Huamán Camayo, O.M.I. | Auxiliary Bishop of Huancayo, Peru | Archbishop |
| 51.2 | Appointed | Luis Alberto Huamán Camayo, O.M.I. | Titular Bishop of Tepelta | Archbishop of Huancayo, Peru |
| 60.4 | Appointed | Carlos Alberto Salcedo Ojeda, O.M.I. | Bishop of Huancavélica, Peru |
| 51.7 | Ordained Bishop | Juan José Salaverry Villarreal, O.P. | Titular Bishop of Acelum | Auxiliary Bishop of Lima, Peru |
| 22 May | 60.8 | Installed | Carlos Enrique Curiel Herrera, Sch. P. | Bishop of Carora, Venezuela |
| 60.8 | Succeeded | Alessandro Damiano | Archbishop of Agrigento, Italy |
| 55.6 | Appointed | Lawrence Subrata Howlader, C.S.C. | Apostolic Administrator of Barishal, Bangladesh | Archbishop of Chattogram, Bangladesh |
| 55.6 | Installed | Lawrence Subrata Howlader, C.S.C. | Archbishop of Chattogram, Bangladesh |
| 75.0 | Retired | Francesco Montenegro | Archbishop of Agrigento, Italy | Cardinal, Archbishop Emeritus |
| 64.5 | Installed | Francisco Javier Múnera Correa, I.M.C. | Archbishop of Cartagena, Colombia |
| 58.8 | Appointed | Fulgence Muteba Mugalu | Archbishop of Lubumbashi, Congo (Dem. Rep.) |
| 58.8 | Appointed | Fulgence Muteba Mugalu | Apostolic Administrator of Kilwa-Kasenga, Congo (Dem. Rep.) | Archbishop of Lubumbashi, Congo (Dem. Rep.) |
| 73.1 | Appointed | Gennaro Pascarella | Bishop of Ischia, Italy | Bishop Emeritus of Pozzuoli, Italy |
| 80.0 | Ceased | Ubaldo Ramón Santana Sequera, F.M.I. | Apostolic Administrator of Carora, Venezuela | Archbishop Emeritus of Maracaibo, Venezuela |
| 52.7 | Appointed | Pius Sin Hozel | Auxiliary Bishop of Busan {Pusan}, Korea (South) |
| 52.7 | Appointed | Pius Sin Hozel | Titular Bishop of Belesasa | Auxiliary Bishop of Busan {Pusan}, Korea (South) |
| 60.0 | Ordained Bishop | Ranko Vidović | Bishop of Hvar (-Brac e Vis), Croatia |
| 23 May | 75.4 | Appointed | Gilles Côté, S.M.M. | Apostolic Administrator of Daru-Kiunga, Papua New Guinea | Bishop Emeritus |
| 75.4 | Retired | Gilles Côté, S.M.M. | Bishop of Daru-Kiunga, Papua New Guinea | Bishop Emeritus |
| 53.1 | Appointed | Joseph Tarife Durero, S.V.D. | Bishop of Daru-Kiunga, Papua New Guinea |
| 51.2 | Ordained Bishop | Josif Printezis | Archbishop of Naxos, Andros, Tinos e Mykonos, Greece |
| 24 May | 75.7 | Retired | Max Leroy Davis | Bishop of Australia, Military | Bishop Emeritus |
| 80.7 | Installed | Enrico Feroci | Cardinal, Cardinal-Deacon of Santa Maria del Divino Amore a Castel di Leva |
| 67.5 | Appointed | Christopher Charles Prowse | Apostolic Administrator of Australia, Military | Archbishop of Canberra and Goulburn, Australia |
| 25 May | 86.5 | Died | Grégoire Pierre XX (Krikor) Ghabroyan, I.C.P.B. † | Patriarch of Cilicia (Armenian), Lebanon |
| 63.8 | Died | José Melitón Chávez † | Bishop of Concepción, Argentina |
| 26 May | 54.5 | Installed | Luis Alberto Barrera Pacheco, M.C.C.I. | Bishop of Callao, Peru |
| 80.0 | Died | Arturo de Jesús Correa Toro † | Bishop Emeritus of Ipiales, Colombia |
| 73.2 | Appointed | Boutros Marayati | Patriarchal Administrator of Cilicia (Armenian), Lebanon | Archbishop of Alep [Beroea, Halab] (Armenian), Syria |
| 65.6 | Ceased | Robert Francis Prevost, O.S.A. | Apostolic Administrator of Callao, Peru | Pope (Roma {Rome}, Italy) |
| 27 May | 60.3 | Installed | Galo Fernández Villaseca | Bishop of Talca, Chile |
| 56.1 | Appointed | Aurelio García Macías | Under Secretary of the Congregation for Divine Worship and the Discipline of the Sacraments | Under Secretary of the Dicastery for Divine Worship and the Discipline of the Sacraments |
| 56.1 | Appointed | Aurelio García Macías | Titular Bishop of Rotdon | Under Secretary of the Dicastery for Divine Worship and the Discipline of the Sacraments |
| 88.6 | Died | Heinrich Janssen † | Auxiliary Bishop Emeritus of Münster, Germany |
| 71.2 | Appointed | Arthur Roche | Prefect of the Congregation for Divine Worship and the Discipline of the Sacraments | Cardinal, Prefect of the Dicastery for Divine Worship and the Discipline of the Sacraments |
| 55.6 | Appointed | Vittorio Francesco Viola, O.F.M. | Secretary of the Congregation for Divine Worship and the Discipline of the Sacraments | Secretary of the Dicastery for Divine Worship and the Discipline of the Sacraments |
| 55.6 | Appointed | Vittorio Francesco Viola, O.F.M. | Archbishop (Personal Title) | Secretary of the Dicastery for Divine Worship and the Discipline of the Sacraments |
| 28 May | 56.5 | Ordained Bishop | Guillermo Antonio Cornejo Monzón | Titular Bishop of Decoriana | Auxiliary Bishop of Lima, Peru |
| 60.6 | Appointed | Gregory William Gordon | Auxiliary Bishop of Las Vegas, Nevada, USA | Auxiliary Bishop of Las Vegas, Nevada, USA |
| 60.6 | Appointed | Gregory William Gordon | Titular Bishop of Nova Petra | Auxiliary Bishop of Las Vegas, Nevada, USA |
| 83.6 | Died | Joseph Nunzio Latino † | Bishop Emeritus of Jackson, Mississippi, USA |
| 29 May | 58.7 | Ordained Bishop | Giampio Luigi Devasini | Bishop of Chiavari, Italy |
| 46.1 | Appointed | Francisco Figueroa Cervantes | Auxiliary Bishop of Zamora, Michoacán, México |
| 46.1 | Appointed | Francisco Figueroa Cervantes | Titular Bishop of Lamasba | Auxiliary Bishop of Zamora, Michoacán, México |
| 55.5 | Installed | Mauro Maria Gambetti, O.F.M. Conv. | Cardinal-Deacon of Santissimo Nome di Maria al Foro Traiano | Cardinal, President of the Fabric of St. Peter |
| 53.7 | Ordained Bishop | Joseph-Bernard Likolo Bokal’Etumba | Bishop of Lisala, Congo (Dem. Rep.) |
| 57.0 | Ceased | Ernest Ngboko Ngombe, C.I.C.M. | Apostolic Administrator of Lisala, Congo (Dem. Rep.) | Archbishop of Mbandaka-Bikoro, Congo (Dem. Rep.) |
| 69.7 | Died | Cornelius Sim † | Cardinal, Vicar Apostolic of Brunei |
| 65.9 | Ordained Bishop | Siphiwo Devilliers Paul Vanqa, S.A.C. | Bishop of Queenstown, South Africa |
| 30 May | 57.7 | Ordained Bishop | Maksimilijan Matjaž | Bishop of Celje, Slovenia |
| 31 May | 57.4 | Appointed | Lazarus Vitalis Msimbe, S.D.S. | Bishop of Morogoro, Tanzania |
| 60.5 | Appointed | Arulselvam Rayappan | Bishop of Salem, India |