| Gattung | Titel | Komponist | Komponiert |
|---|
| Oper | Macbeth | Ernest Bloch | 1904-09 |
| Oper | Madama Butterfly | Giacomo Puccini | 1901-03, rev. 1904 und 1907 |
| Oper | Madame Butterfly | Giacomo Puccini | 1901-03, rev. 1904 und 1907 |
| Operette | Madame la lune | Paul Lincke | 1899 |
| Operette | Madame Pompadour | Leo Fall | 1922 |
| Oper | Madame Sans-Gêne | Umberto Giordano | 1914-15 |
| Oper | Mahomet II | Gioacchino Rossini | 1820 |
| Oper | Maiskaja notsch [Майская ночь] | Nikolai Andrejewitsch Rimski-Korsakow | 1878-79 |
| Oper | Manon Lescaut | Daniel-François-Esprit Auber | 1856 |
| Oper | Manru | Ignaz Jan Paderewski | 1892-1901 |
| Oper | Maometto II | Gioacchino Rossini | 1820 |
| Oper | Maometto secondo | Gioacchino Rossini | 1820 |
| Oper | Mare and her Son | Tauno Pylkkänen | 1943 |
| Oper | Mare ja hänen poikansa | Tauno Pylkkänen | 1943 |
| Oper | Mare und ihr Sohn | Tauno Pylkkänen | 1943 |
| Oper | Margarethe von Anjou | Giacomo Meyerbeer | 1820 |
| Oper | Margherita d'Anjou | Giacomo Meyerbeer | 1820 |
| Oper | Margherita da Cortona | Licinio Refice | 1937 |
| Oper | Maria de Buenos Aires | Ástor Piazzolla | 1968 |
| Oper | María del Carmen | Enrique Granados | 1898 |
| Oper | Mariannes Allüren | Henri Sauguet | 1954 |
| Oper | Maria Padilla | Gaetano Donizetti | 1841 |
| Oper | Maria regina d'Inghilterra | Giovanni Pacini | 1843 |
| Oper | Maria Stuarda | Gaetano Donizetti | 1834 |
| Oper | Mariken de Nimégue | Bohuslav Martinů | 1933, rev. 1934 |
| Oper | Mariken of Nimégue | Bohuslav Martinů | 1933, rev. 1934 |
| Oper | Mariken von Nimwegen | Bohuslav Martinů | 1933, rev. 1934 |
| Oper | Mariken z Nimègue | Bohuslav Martinů | 1933, rev. 1934 |
| Oper | Marion Delorme | Amilcare Ponchielli | 1885, rev. 1885 |
| Oper | Martha oder Der Markt von Richmond | Friedrich von Flotow | 1847 |
| Oper | Masepa [Мазепа] | Peter Iljitsch Tschaikowski | 1883 |
| Operette | Maske in Blau | Fred Raymond | 1937 |
| Operette | Mask in Blue | Fred Raymond | 1937 |
| Oper | Massimilla Doni | Othmar Schoeck | 1934/35 |
| Oper | Ma Tante Aurore ou Le Roman impromptu | François-Adrien Boieldieu | 1802 ? |
| Oper | Mathilde de Shabran ou Beauté et cœur de fer | Gioacchino Rossini | 1820-21 |
| Oper | Mathilde von Shabran oder Die Schönheit und das Eisenherz | Gioacchino Rossini | 1820-21 |
| Oper | Matilde di Shabran, ossia Bellezza e cuor di ferro | Gioacchino Rossini | 1820-21 |
| Oper | Matilde of Shabran, or Beauty and Heart of Iron | Gioacchino Rossini | 1820-21 |
| Oper | Mavra | Igor Fjodorowitsch Strawinski | 1921/22 |
| Oper | Mawra [Мавра] | Igor Fjodorowitsch Strawinski | 1921/22 |
| Oper | May Night | Nikolai Andrejewitsch Rimski-Korsakow | 1878-79 |
| Oper | Mazepa | Peter Iljitsch Tschaikowski | 1883 |
| Oper | Mazeppa | Peter Iljitsch Tschaikowski | 1883 |
| Oper | Medea | Marc-Antoine Charpentier | 1693-94 |
| Oper | Médée | Marc-Antoine Charpentier | 1693-94 |
| Oper | Medonte | Josef Mysliveček | 1780 |
| Oper | Mefistofele | Arrigo Boito | 1868, rev. 1876 |
| Oper | Mehmet | Giovanni Battista Sammartini | 1732 |
| Oper | Memet | Giovanni Battista Sammartini | 1732 |
| Oper | Mendi Mendiyan | José Maria Usandizaga | ? |
| Oper | Mephistopheles | Arrigo Boito | 1868, rev. 1876 |
| Oper | Mignon | Ambroise Thomas | 1863-66, rev. 1866, 1869 und 1870 |
| Oper | Miguel Mañara, ou Don Juan de Mañara | Henri Tomasi | 1936 |
| Singspiel | Miriways | Georg Philipp Telemann | 1728 |
| Oper | Mitridate, Rè di Ponto | Wolfgang Amadeus Mozart | 1770 |
| Oper | Mitridates, König von Pontos | Wolfgang Amadeus Mozart | 1770 |
| Oper | Mjortwye duschi [Мёртвые души] | Rodion Konstantinowitsch Schtschedrin | 1966-77 |
| Oper | Mlada [Млада] | Nikolai Andrejewitsch Rimski-Korsakow | 1889-90 |
| Oper | Moby Dick | Jake Heggie | 2010 |
| Oper | Moby-Dick | Jake Heggie | 2010 |
| Oper | Mohammed der Zweite | Gioacchino Rossini | 1820 |
| Oper | Montezuma | Carl Heinrich Graun | 1754-55 |
| Oper | Mord im Dom | Ildebrando Pizzetti | 1955-57 |
| Oper | Morgen | Tadeusz Baird | ? |
| Oper | Moses | Zsolt Durkó | 1976-77 |
| Oper | Motezuma | Antonio Vivaldi | spätestens 1733 |
| Oper | Mózes | Zsolt Durkó | 1976-77 |
| Oper | Murder in the Cathedral | Ildebrando Pizzetti | 1955-57 |