| Birth Date: | 12 January 1928 |
| Birth Place: | Lappeenranta, Finland |
| Death Date: | 2 July 2003 (aged 75) |
| Death Place: | Pori, Finland |
| Height: | 172 cm |
| Weight: | 63–70 kg |
| Sport: | Boxing |
| Show-Medals: | yes |
Erkki Aarno Mallenius (12 January 1928 – 2 July 2003) was a Finnish amateur boxer who won a bronze medal in the light welterweight division at the 1952 Olympics.
Mallenius took up boxing in 1945 and in 1946 won the Finnish junior lightweight title. He never held a senior national title, and qualified to the Helsinki Olympics by winning the 1952 Olympic trials. At the Olympics he won his first two bouts, but broke a carpal bone in a hand in the second one, and hence withdrew from the semifinal and retired from boxing. He then worked as a boxing coach and a building contractor. In 2008 he was inducted into the Finnish Boxing Hall of Fame.