Marcus Laborne Mattioli (born 18 October 1960 in Belo Horizonte[1]) is a former international freestyle and butterfly swimmer from Brazil, who participated in the 1980 Summer Olympics for his native country.

There he won the bronze medal in the men's 4×200-metre freestyle relay event at the 1980 Summer Olympics, alongside Jorge Fernandes, Cyro Delgado, and Djan Madruga.

[5] Mattioli won the bronze medal in the men's 4×200-metre freestyle relay event at the 1980 Summer Olympics, alongside Jorge Fernandes, Cyro Delgado, and Djan Madruga, with a time of 7:29.30.

[6] At the 1981 Summer Universiade, held in Bucharest, Mattioli won two bronze medals in the 4×100-metre freestyle and 4×100-metre medley relays.

[11] Mattioli still swim, now breaking world records in the Masters category.