LMB as an abbreviation may stand for:
- Laboratory of Molecular Biology, a research institute in Cambridge, England
- Liga Mexicana de Beisbol, the Mexican Baseball League
- Left Mouse Button on a mouse (computing)
- La Martiniere College for Boys, Kolkata
- Lois McMaster Bujold, science fiction and fantasy author
- Line Mode Browser, the first multi-platform web browser
- Leptomycin B, an inhibitor of protein export from the cell nucleus