| Thora Signe Grahl-Nielsen | |
| Occupation: | Norwegian politician |
| Birth Date: | 29 June 1901 |
Thora Grahl-Nielsen (29 June 1901 – 19 April 1976) was a Norwegian politician for the Conservative Party.
She served as a deputy representative to the Parliament of Norway from Bergen during the terms 1950–1953, 1954–1957 and 1958–1961. In total she met during 39 days of parliamentary session.