TMN is an abbreviation for:
- The Movie Network, a Canadian television network
- Telecomunicações Móveis Nacionais, SA, a Portuguese telecom
- Telecommunications Management Network, a network protocol
- TrackMania Nations, a computer game.
- Texas Moratorium Network, an advocacy organization dealing with the death penalty
- TMN Group plc, an email marketing company.
- TM Network, aka TMN between 1990 & 1994, Japanese pop band
- The Morning News, an online magazine