- Abheiter, Hermann
- Absil, Jean
- Abt, Franz
- Adam, Adolphe
- Adams, Stephen
- Adler, Samuel
- Agostini, Pietro Simone
- Albéniz, Isaac
- Albinoni, Tomaso
- Alfano, Franco
- Alnaes, Eyvind
- Alvarez, Fermin María
- Alveri, Giovanni Battista
- Amadei, Albert
- Amalia, Anna
- Ambrose, Paul
- Amram, David Werner
- Andrews, Mark
- Aniello, Pancrazio
- Anonymous English Composers
- Anonymous French Composers
- Anonymous German Composers
- Anonymous Italian Composers
- Anonymous Spanish Composers
- Ansorge, Conrad
- Araia, Francesco
- Arditi, Luigi
- Argento, Dominick
- Arne, Thomas Augustine
- Arnim, Bettina von
- Arnold, Carl
- Arrieta, Emilio
- Asensi, Juan Miguel
- Asioli, Bonifazio
- Astorga, Emanuele d’
- Attenhofer, Carl
- Attwood, Thomas
- Auber, Daniel
- Aubert, Louis
- Auric, Georges
- Ayres, Frederic
- Bach, Carl Philipp Emanuel
- Bach, Johann Sebastian
- Bachelet, Alfred
- Bachlund, Gary
- Backer-Grøndahl, Agathe Ursula
- Bacon, Ernst
- Bairstow, Edward Cuthbert
- Baksa, Robert F.
- Balfe, Michael William
- Ballif, Claude
- Baltar, Francisco
- Bantock, Granville Ransome
- Barab, Seymour
- Barber, Samuel
- Barbieri, Francisco Asenjo
- Bartók, Béla
- Bartolí-Soler, Salvador
- Basili, Basilio
- Bassani, Giovanni Battista
- Baumgartner, Wilhelm
- Bautista, Julián
- Bax, Arnold Edward Trevor
- Baxter, Garth
- Beach, Amy Marcy
- Beck, John Ness
- Becker, Reinhold
- Beeson, Jack Hamilton
- Beethoven, Ludwig van
- Behrend, Arthur Henry
- Bellini, Vincenzo
- Bemberg, Herman
- Bembo, Antonia
- Benaigues y Pujol, Josep Maria
- Bencini, Pietro Paolo
- Benda, Georg
- Benedict, Julius
- Berg, Alban
- Berg, Natanael
- Berger, Hugo
- Berger, Ludwig
- Berio, Luciano
- Berkeley, Lennox
- Berlioz, Hector
- Bernstein, Leonard
- Beydts, Louis
- Bezanson, Phillip Thomas
- Bezold, Gustav von
- Bishop, Henry Rowley
- Bizet, Georges
- Blank, Allan
- Blanquer Ponsada, Amando
- Blasco Compans, Justo
- Blech, Leo
- Bliss, Arthur
- Blitzstein, Marc
- Blomberg, Adolf
- Blon, Franz von
- Blow, John
- Bohm, Carl