Félix-Alexandre Guilmant (French: [gilmɑ̃]; 12 March 1837 – 29 March 1911) was a French organist and composer. He was the organist of La Trinité from 1871 until 1901. A noted pedagogue, performer, and improviser, Guilmant helped found the Schola Cantorum in Paris. He was appointed as Professor of Organ at the Paris Conservatoire in 1896.
Guilmant was born in Boulogne-sur-Mer. A student of his father, then of the Belgian master Jacques-Nicolas Lemmens, he became an organist and teacher in his place of birth.
In 1871 he was appointed to play the organ regularly at la Trinité church in Paris, and this position he held for 30 years. Guilmant was known for his improvisations, both in the concert and church setting. His inspiration came from gregorian chants, and he was greatly noted amongst his colleagues for his mastery of the melodies. From then on, Guilmant followed a career as a virtuoso; he gave concerts in the United States (the first major French organist to tour that country), and in Canada, as well as in Europe, making especially frequent visits to England. His American achievements included a 1904 series of no fewer than 40 recitals on the largest organ in the world, the St. Louis Exposition Organ, now preserved as the nucleus of Philadelphia's Wanamaker Organ.
With his younger colleague André Pirro, Guilmant published a collection of scores, Archives des Maîtres de l'Orgue (Archives of the Masters of the Organ), a compilation of the compositions of numerous pre-1750 French composers. The collection was printed in ten volumes, the first in 1898 and the last (which Guilmant did not live to finalize) in 1914. Guilmant provided a rather similar survey of organ pieces by foreign composers, publishing l'École classique de l'Orgue (Classical School of the Organ). These anthologies, despite all the musicological developments which have taken place since Guilmant's own time, remain very valuable sources of early music.