The Light flyweight competition was the lightest class featured at the 2009 World Amateur Boxing Championships, and was held at the Mediolanum Forum. Flyweights were limited to a maximum of 48 kilograms in body mass.
| Gold | Pürevdorjiin Serdamba |
| Silver | David Ayrapetyan |
| Bronze | Li Jiazhao |
| Shin Jong-Hun |
Łukasz Maszczyk (quarterfinals)
Nanao Singh Thokchom (second round)
Patrick Barnes (second round)
Paulo Carvaho (third round)
Hovhannes Danielyan (quarterfinals)
Redouane Bouchtouk (third round)
José Kelvin de la Nieve Linares (quarterfinals)
Ferhat Pehlivan (second round)