He was born in Mendorf near Altmannstein, Landkreis Eichstätt, Bavaria, and studied theology at the University of Ingolstadt, continuing his studies in Italy from 1787. He was closely associated with the Bavarian Illuminati of Adam Weishaupt while a student in Ingolstadt, and the ideals of the French Enlightenment were a strong influence on his philosophy as a musician as corroborated by his famed Zibaldone or "Notebooks" compiled toward the end of his career.
Shortly thereafter, he took music lessons with Carlo Lenzi, and later with Ferdinando Bertoni. He moved to Bergamo in 1802 and was appointed maestro di cappella at the Cathedral of Bergamo, succeeding his old teacher Lenzi. He held the post until his death, and became a central figure in the city's musical life, organizing concerts and introducing Ludwig van Beethoven's music there. He was music teacher to Gaetano Donizetti. By the end of his life, he was blind. He died in Bergamo and is buried in the Basilica di Santa Maria Maggiore there, just in front of the tomb of his famous pupil.
Mayr's astonishing list of works, among which are almost seventy operas, are rarely performed today.
See List of compositions by Simon Mayr and List of operas by Mayr
Ginevra di Scozia - Elisabeth Vidal (soprano); Daniela Barcellona (mezzo-soprano); Antonio Siragusa (tenor); Luca Grassi (baritone); Giuseppina Piunti (soprano); Marco Lazzara (countertenor); Orchestra del Teatro Verdi di Trieste; Tiziano Severini (conductor). Label: Opera Rara ORC23,
Fedra (Chiaudani, Nelsen, Zagorski, Lee; Schaller) OEHMS Classics 920,
La Rosa Bianca e la Rosa Rossa (Antonacci, Anselmi, Serraicocca, Canonici, Facini; Briccetti) Fonit Cetra RFCD 2007,
Verter (Herrmann, Gemmabella, Cicchetti, Salsi, Zarelli; Terracini) Bongiovanni GB 2343-4.,
Sisara Accademia I Filarmonici di Verona, Simon Mayr Chor conducted by Franz Hauk Guild GmbH 2004,
Medea in Corinto (Eaglen, Kenny, Ford, Miles; Parry) Opera Rara ORC11 1993,
Konzertmitschnitte von Werken von Johann Simon Mayr. Wilhelm Schmailzl, Karlskron 1996,
Samuele Fono-Schallplattengesellschaft, Laer 1997,
La Passione Kammerorchester Ingolstadt Guild 2002,
David in Spelunca Engaddi Naxos 2008,
L'amor coniugale, Naxos Oper, 2008,
Tobiae Matrimonium Simon Mayr Chor + Ensemble, Naxos 2009,
Medea in Corinto Theater St. Gallen, Oehmsclassic 2010