| Dag Ole Thomassen | |
| Fullname: | Dag Ole Høvring Thomassen |
| Birth Date: | 28 August 1986 |
| Birth Place: | Skien, Norway |
| Youthclubs2: | Pors Grenland |
| Position: | Goalkeeper |
| Years1: | 2003–2007 |
| Years2: | 2008–2010 |
| Years3: | 2011–2012 |
| Caps1: | 39 |
| Goals1: | 0 |
| Caps2: | 5 |
| Goals2: | 0 |
| Nationalteam1: | Norway U16 |
| Nationalteam2: | Norway U17 |
| Nationalteam3: | Norway U18 |
| Nationalteam4: | Norway U19 |
| Nationalcaps1: | 6 |
| Nationalgoals1: | 0 |
| Nationalcaps2: | 8 |
| Nationalgoals2: | 0 |
| Nationalcaps3: | 6 |
| Nationalgoals3: | 0 |
| Nationalcaps4: | 1 |
| Nationalgoals4: | 0 |
| Pcupdate: | 20 May 2009 |
| Ntupdate: | 20 May 2009 |
Dag Ole Thomassen (born 28 June 1986) is a retired Norwegian football goalkeeper. He started and ended his senior career in Pors Grenland, intermittently playing first-tier football for Odd Grenland.[1]