The St. Francis Mass is the shorter name for the Missa sub titulo Sancti Francisci Seraphici (Klafsky I:23, MH 826) composed by Michael Haydn.

[1] The score calls for a quartet of vocal soloists, mixed choir, 2 oboes, bassoon, 2 horns, 2 trumpets, timpani, and strings with an organ to play basso continuo.

Many composers have prolonged the setting of the word passus in the Credo through the use of techniques such as melisma, syncopation, and suspension.

In this mass, however, Haydn prolongs the word simply by using two "longer note values than have occurred earlier in the setting".

[2] The mass was published in 1917 as Volume 45 of the Denkmäler der Tonkunst in Österreich, edited by Anton Maria Klafsky.