| Gaëtan Karlen | |
| Birth Date: | 1993 6, df=yes |
| Birth Place: | Sion, Switzerland |
| Position: | Forward |
| Youthclubs1: | Conthey[1] |
| Youthclubs2: | Sion |
| Years1: | 2013–2015 |
| Clubs1: | Sion |
| Caps1: | 17 |
| Goals1: | 1 |
| Years2: | 2014 |
| Clubs2: | → Biel-Bienne (loan) |
| Caps2: | 17 |
| Goals2: | 9 |
| Years3: | 2015 |
| Clubs3: | Thun |
| Caps3: | 16 |
| Goals3: | 2 |
| Years4: | 2015–2016 |
| Clubs4: | Biel-Bienne |
| Caps4: | 17 |
| Goals4: | 4 |
| Years5: | 2016–2020 |
| Clubs5: | Neuchâtel Xamax |
| Caps5: | 77 |
| Goals5: | 28 |
| Years6: | 2020–2023 |
| Clubs6: | Sion |
| Caps6: | 72 |
| Goals6: | 11 |
| Nationalyears1: | 2010 |
| Nationalteam1: | Switzerland U18 |
| Nationalcaps1: | 4 |
| Nationalgoals1: | 1 |
| Nationalyears2: | 2011 |
| Nationalteam2: | Switzerland U19 |
| Nationalcaps2: | 4 |
| Nationalgoals2: | 1 |
| Nationalyears3: | 2013 |
| Nationalteam3: | Switzerland U20 |
| Nationalcaps3: | 8 |
| Nationalgoals3: | 2 |
| Nationalyears4: | 2014 |
| Nationalteam4: | Switzerland U21 |
| Nationalcaps4: | 1 |
| Nationalgoals4: | 0 |
| Club-Update: | 5 June 2023 |
Gaëtan Karlen (born 7 June 1993) is a Swiss professional footballer who plays as a forward.
Gaëtan's brother Gregory is also a professional footballer. They have both played for Sion and Thun.