MTD may refer to:
- Argentine unemployed workers movement (Movimiento de Trabajadores Desocupados) — see Piquetero
- A mass transit district, such as the Champaign-Urbana Mass Transit District or the Metropolitan Transit District
- The Makkal Tamil Desam Katchi, "People's Tamil Land Party", a political party in Tamil Nadu, India
- Metal Trades Department of the AFL-CIO
- MTD Products, Inc., a manufacturer of outdoor power equipment such as the Cub Cadet in Cleveland, Ohio, United States
- MTD-f, a minimax search algorithm
- Memory Technology Device, are those class of devices like flash chips, which are increasingly finding their way into embedded devices
- Month-To-Date, as in Year-To-Date or Quarter-To-Date
- Michael Tobias Design, a bass player and guitar company
- The MTD (mobile network) former manual mobile network in Sweden, Norway and Denmark
- Maximum tolerated dose in drug development
- Moralistic therapeutic deism
- Methadone Methadone
- MTD has been used in recent years to refer to hyperfunctional muscularture effecting the voice and is an abbreviation of Muscle Tension Dysphonia
- MTD (Modern Tool and Die), a manufacturer of outdoor power equipment for the mass market