| 139201 | December 9 | Birth | 1980 – Simon Helberg, American actor, producer, and screenwriter |
| 139202 | December 9 | Birth | 1980 – Ryder Hesjedal, Canadian cyclist |
| 139203 | December 9 | Birth | 1981 – Mardy Fish, American tennis player |
| 139204 | December 9 | Birth | 1981 – Dia Mirza, Indian model, actress, and producer |
| 139205 | December 9 | Birth | 1982 – Tamilla Abassova, Russian cyclist |
| 139206 | December 9 | Birth | 1982 – Nathalie De Vos, Belgian runner |
| 139207 | December 9 | Birth | 1982 – Ryan Grant, American football player |
| 139208 | December 9 | Birth | 1982 – Bastian Swillims, German sprinter |
| 139209 | December 9 | Birth | 1982 – Meryll Soriano, Filipino actress |
| 139210 | December 9 | Birth | 1983 – Jermaine Beckford, English-Jamaican footballer |
| 139211 | December 9 | Birth | 1983 – Neslihan Demir Darnel, Turkish volleyball player |
| 139212 | December 9 | Birth | 1983 – Dariusz Dudka, Polish footballer |
| 139213 | December 9 | Birth | 1984 – Michael Adam, German politician |
| 139214 | December 9 | Birth | 1984 – Ángel Guirado, Spanish–Filipino footballer |
| 139215 | December 9 | Birth | 1984 – Leon Hall, American football player |
| 139216 | December 9 | Birth | 1985 – Wil Besseling, Dutch golfer |
| 139217 | December 9 | Birth | 1986 – Wanda Nara, Argentinian model |
| 139218 | December 9 | Birth | 1987 – Kostas Giannoulis, Greek footballer |
| 139219 | December 9 | Birth | 1987 – Mat Latos, American baseball player |
| 139220 | December 9 | Birth | 1987 – Hikaru Nakamura, Japanese-American chess player |
| 139221 | December 9 | Birth | 1988 – Kwadwo Asamoah, Ghanaian footballer |
| 139222 | December 9 | Birth | 1989 – Elle Evans, American model and actress |
| 139223 | December 9 | Birth | 1990 – LaFee, German singer-songwriter |
| 139224 | December 9 | Birth | 1990 – Daundre Barnaby, Jamaican-Canadian runner (d. 2015) |
| 139225 | December 9 | Birth | 1991 – Prince Joachim of Belgium, Archduke of Austria-Este |
| 139226 | December 9 | Birth | 1991 – Choi Minho, South Korean singer, dancer, and actor (Shinee) |
| 139227 | December 9 | Birth | 1993 – Mark McMorris, Canadian snowboarder |
| 139228 | December 9 | Birth | 1993 – Laura Smulders, Dutch cyclist |
| 139229 | December 9 | Birth | 1995 – McKayla Maroney, American gymnast |
| 139230 | December 9 | Birth | 1996 – Mykayla Skinner, American gymnast |