| Federico Elduayén | |
| Fullname: | Federico Martín Elduayén Saldaña |
| Birth Date: | June 25, 1977 |
| Birth Place: | Fray Bentos, Uruguay |
| Position: | Goalkeeper |
| Youthclubs1: | Peñarol |
| Years1: | 1999–2005 |
| Years2: | 2005–2009 |
| Years3: | 2010 |
| Years4: | 2011 |
| Years5: | 2012–2013 |
| Years6: | 2013–2014 |
| Years7: | 2015 |
| Clubs4: | Unión Española |
| Clubs5: | Universitario de Sucre |
| Clubs6: | Guabirá |
| Clubs7: | Universitario de Sucre |
| Caps1: | 95 |
| Caps2: | 118 |
| Caps3: | 35 |
| Caps4: | 13 |
| Caps5: | 36 |
| Caps6: | 36 |
| Goals1: | 0 |
| Goals2: | 0 |
| Goals3: | 0 |
| Goals4: | 0 |
| Goals5: | 0 |
| Goals6: | 0 |
| Nationalyears1: | 2002 |
| Nationalteam1: | Uruguay |
| Nationalcaps1: | 1 |
| Nationalgoals1: | 0 |
Federico Martín Elduayén Saldaña (born June 25, 1977) is an Uruguayan football former goalkeeper. His nickname is "Vikingo" (Viking).
He began his career in the youth squads of Peñarol. He made his professional debut in 1999, in the Copa Mercosur defending Peñarol against Vasco Da Gama in Brazil. Elduayén participated in six straight Copa Libertadores editions with Peñarol from 2000–2005.
He was the team's starting goalkeeper until 2005 when he lost his job and moved to Universidad de Concepción in Chile. Ever since joining the Chilean side he became the starting goalkeeper there. He renewed his contract until the end of the 2009 season. The following year Elduayén transferred to O'Higgins where he played for one season, before signing with Unión Española. In 2012, he landed in Bolivia and signing for Universitario de Sucre.
Elduayen made one appearance for the Uruguay national football team and was part of the squad for the 2002 FIFA World Cup.