Police found Di Maulo, 70, dead in the driveway of his residence in Blainville on Nov. 4.
A significant media presence and a handful of curious onlookers gathered outside the church. They watched six silver Cadillacs adorned with flowers leave the site behind the hearse.
A few police officers discreetly kept an eye on the proceedings.
Di Maulo has allegedly been a key figure in Montreal's organized crime since the '70s.
Investigative journalist Julian Sher told CBC News that Di Maulo's death revealed the complicated chessboard of Montreal's organized crime.
Sher said Di Maulo was in the Mafia's Calabrian branch, which ran Montreal in the 1970s in opposition to the Mob-linked Rizzuto family.
Di Maulo escaped a jail sentence in 1971 after a successful appeal on a triple murder case that was committed in his bar, La Casa Loma. The bar was located near Saint-Laurent Boulevard in Montreal at the time.
Di Maulo's death comes a month after Montreal's Sicilian Mob boss, Vito Rizzuto, was released from prison and returned to Canada after serving an eight-year sentence for his role in the killing of three leaders of New York's Bonanno crime family.