| Subcategories | | Maayani, Ami | MacCunn, Hamish | MacDowell, Edward Alexander | MacMillan, Ernest Alexander Campbell, Sir | MacMillan, James | Mace, Thomas |
| Maceda, José | Macfarren, George Alexander, Sir | Macfarren, Walter Cecil | Machaut, Guillaume de | Mackenzie, Alexander Campbell, Sir | Maconchy, Elizabeth, Dame |
| Macque, Giovanni de | Maderna, Bruno | Maderna, Osmar Héctor | Madetoja, Leevi Antti | Maegaard, Jan Carl Christian | Maessens, Pieter |
| Magle, Frederik | Magnard, Lucien Denis Gabriel Albéric | Mahler, Alma Schindler | Mahler, Gustav | Maier, Michael | Maklakiewicz, Jan Adam |
| Malawski, Artur | Malec, Ivo | Malipiero, Gian Francesco | Malling, Otto Valdemar | Malvezzi, Cristofano | Mamangakis, Nicos |
| Manchicourt, Pierre de | Mancinelli, Luigi | Mancini, Francesco | Mancini, Henry | Manfredini, Francesco Onofrio | Manfredini, Vincenzo |
| Manziarly, Marcelle de | Manzoni, Giacomo | Marais, Marin | Marcello, Alessandro | Marcello, Benedetto | Marchetto da Padova |
| Marenzio, Luca | Mariani, Angelo Maurizio Gaspare | Marini, Biagio | Marino, Carlo Antonio | Marinuzzi, Gino, Jr. | Marinuzzi, Gino, Sr. |
| Mariétan, Pierre | Markevitch, Igor | Maros, Miklós | Maros, Rudolf | Marpurg, Friedrich Wilhelm | Marsalis, Wynton |
| Marschner, Heinrich August | Marsh, John | Marshall, Ingram | Marshall-Hall, George William Louis | Martin, Frank | Martin?, Bohuslav Jan |
| Martinez, Odaline de la | Martini, Giovanni Battista, Padre | Martini, Johann Paul Aegidius | Martini, Johannes | Martino, Donald James | Martinon, Jean |
| Martirano, Salvatore Giovanni | Martucci, Giuseppe | Martín y Soler, Atanasio Martín Ignacio Vicente Tadeo Francisco Pellegrín | Marx, Adolf Bernhard | Marx, Joseph | Marx, Karl |
| Masaoka, Miya | Mascagni, Pietro | Maschera, Florentio | Mason, Daniel Gregory | Mason, Lowell | Massenet, Jules Emile Frédéric |
| Massé, Victor | Mata, Eduardo | Mather, James Bruce | Matheus de Sancto Johanne | Mathews, Max Vernon | Mathias, William James |
| Matsudaira, Yoritsune | Matteis, Nicola the Elder | Matteis, Nicola the Younger | Matteo da Perugia | Mattheson, Johann | Matthews, Colin |
| Matthews, David | Mauduit, Jacques | Mauersberger, Rudolf | Maw, John Nicholas | Maxwell Davies, Peter | May, Frederick |
| Maynard, John | Mayone, Ascanio | Mayr, Johann Simon | Mayshuet@ | Mayuzumi, Toshirô | Mazzinghi, Joseph |
| Mazzocchi, Domenico | Mazzocchi, Virgilio | Mazzucato, Alberto | McCabe, John | McCartney, Paul@ | McEwan, John Blackwood, Sir |
| McGibbon, William | McPhee, Colin Carhart | Meale, Richard Graham | Mechem, Kirke | Medtner, Nikolai Karlovich | Meester, Louis August Edmond Hendrik de |
| Mellers, Wilfrid Howard | Melli, Domenico Maria | Mellnäs, Arne | Mendelssohn, Arnold Ludwig | Mendelssohn-Bartholdy, Jakob Ludwig Felix | Mendelssohn Hensel, Fanny Cäcilie |
| Mengelberg, Josef Willem | Mengelberg, Karel | Mengelberg, Kurt Rudolf | Mengelberg, Misha | Menotti, Gian Carlo | Messiaen, Olivier |
| Meyerbeer, Giacomo | Miko?aj z Radomia | Milano, Francesco da@ | Milhaud, Darius | Minkus, Ludwig | Moeran, Ernest John |
| Molter, Johann Melchior | Monk, Meredith@ | Monteverdi, Claudio Giovanni Antonio | Moondog | Moore, Douglas Stuart | Moore, Undine Smith |
| Moravec, Paul | Morley, Thomas | Morricone, Ennio | Mozart, Franz Xaver Wolfgang | Mozart, Johann Chrysostom Wolfgang Amadeus | Mozart, Johann Georg Leopold |
| Mumma, Gordon | Munro, Ian | Musgrave, Thea | Mussorgsky, Modest Petrovich | Myaskovsky, Nikolai Yakovlevich | Méfano, Paul |
| Méhul, Étienne-Nicolas | Møller, Peter |
