TMSR, as an acronym, may refer to:
Indian drama
- Tera Mera Saath Rahe, 2021 TV series
- Tera Mera Saath Rahen, 2001 film
Music
- The Most Serene Republic, Canadian indie rock group
Sports
- TMS Ringsted, Danish handball club
Thorium molten salt reactor
- TMSR 500, prior designation of the ThorCon nuclear reactor
- TMSR (Chinese reactor project)
- TMSR-LF1, active experimental reactor