| Martijn Thomassen | |
| Fullname: | Martijn Thomassen |
| Birth Date: | 6 June 1990 |
| Birth Place: | Geldrop, Netherlands |
| Position: | Left back |
| Youthclubs1: | EMK |
| Youthclubs2: | PSV |
| Youthclubs3: | Vitesse/AGOVV |
| Years1: | 2011 - 2012 |
| Clubs1: | AGOVV Apeldoorn |
| Caps1: | 13 |
| Goals1: | 0 |
| Years2: | 2012 - 2013 |
| Clubs2: | FC Eindhoven |
| Caps2: | 1 |
| Goals2: | 0 |
| Club-Update: | 3 August 2013 (UTC) |
Martijn Thomassen (born 6 June 1990 in Geldrop) is a Dutch professional footballer who plays as a defender. He formerly played for AGOVV Apeldoorn and FC Eindhoven. He is currently without a club.