Pierre-Joseph Cassant (6 March 1878 - 17 June 1903) was a French Roman Catholic priest and professed member of the Trappists.
During his novitiate he received the religious name of Marie-Joseph and was known for his strong determination to his studies to fulfil his lifelong wish of being ordained to the priesthood.Cassant suffered from extreme tuberculosis around the time of his ordination and died not long after he was made a priest.
Pope John Paul II celebrated his beatification on 3 October 2004.