In addition to his uncle, he had successively Henri Hess, Camille-Marie Stamaty and Alexis Chauvet as masters of piano, organ, harmony, music composition and fugue.
He made his debut as organist in the cathedral of Uzès (Gard) in 1864, before competing for the position of organist, and later of maître de chapelle of the Verdun Cathedral, that he held from 1868 until 1935, even though the Jacquot-Jeanpierre organ of Rambervillers (Vosges), built in 1898, was dismantled during the First World War to preserve it.
The instrument was rebuilt and inaugurated on 25 March 1935 jointly by the titular master Marcel Dupré and abbot Pierre Camonin who succeeded him in June of the same year.
Grosjean was the maternal grandfather of Élisabeth Brasseur, a choral conductor who founded and directed in Versailles the Chorale Élisabeth Brasseur [fr] from 1920 to her death in 1972.
In the séries Les Maîtres Contemporains de l'Orgue (1912) by abbot Joseph Joubert: