Joseph Charbonneau began his classical studies at the Montfortian Juniorate in Huberdeau and completed them at the Seminary of Sainte-Thérèse. It was at the Grand Séminaire de Montréal that he did his theology. He was ordained priest on June 24, 1916, in his native village, by Archbishop Charles H. Gauthier of Ottawa.

He held a variety of positions that revealed many talents: vicar in Gatineau, student in sociology at the Catholic University of Washington, vicar again in Buckingham, Hawkesbury, and Lefaivre; professor in Montreal where he taught sociology at the Seminary of Philosophy, and finally a student in Rome where he spent two years (1923-1925) obtaining a doctorate in ecclesiastical sciences.

Upon his return, he was appointed first secular superior of the Major Seminary of Ottawa, adding the office of chapter vicar to that of vicar general until his appointment, in 1934, as principal of the École normale de Hull.