- Lindahl, Gerald (Baritone)1
- List, Eugene, 1918-19851
- List, Garrett3
- Listokin, Robert1
- Lockwood, Annea, 1939-1
- Lockwood, Dorothy1
- Lockwood, Normand, 1906-20022
- Loft, Abram, 1922-20193
- Lombardo, Robert, 1932-1
- Lora, Antonio, 1899-19651
- Lora, Edna Elsa1
- Loriod, Jeanne1
- Loriod, Yvonne1
- Los Angeles Philharmonic Orchestra2
- Louwenaar, Karyl1
- Low, Edward1
- López, Elías, 1937-1
- Lucarelli, Bert2
- Luening, Otto, 1900-1996326
- Lundy, Joyce1
- Lybbert, Donald2
- Lynch, Ynez1
- M.I.T. Experimental Electronic Music Studio1
- Maazel, Lorin, 1930-20141
- MacDowell, Edward, 1860-19082
- MacInnis, Donald, 1923-20031
- MacKaye, Percy, 1875-19561
- MacNeice, Louis, 1907-19631
- Macbride, David1
- Macchia, Salvatore2
- Maceda, José1
- Macero, Teo, 1925-20083
- Maclay, Otis1
- Macneil, Alan1
- Madeira, Jean1
- Maderna, Bruno1
- Makanowitzky, Paul, 1920-1
- Makas, Anthony2
- Malec, Ivo1
- Malekpour, Utaco1
- Manhattan Chorus2
- Manzella, Fred1
- Marlowe, Anthony1
- Marshall, Wendell3
- Martin, Alan (Violinist)1
- Martin, Michael (Horn player)1
- Martino, Donald, 1931-20051
- Marx, Josef, 1913-19784
- Marx, Joseph, 1882-19641
- Maslanka, David, 1943-20171
- Mason, Daniel Gregory, 1873-19532
- Massachusetts Institute of Technology1
- Masselos, William3
- Masters, Edgar Lee, 1868-19501
- Mather, Bruce1
- Matsuda, Yoko1
- Matsudaira, Yoritsune, 1907-20011
- Matsuo, Bashō, 1644-16941
- Matsuo, Yoko (Violinist)1
- Maurice, Michael A1