MHD may refer to:
- MHD, former name of the HDTV network for MTV, VH1, and CMT now known as Palladia (MTV Networks)
- Military history detachment
- Doctor of Marine Histories (DMH, formerly Marine Histories Doctorate or MHD), such as issued by Sea Research Society's College of Marine Arts
- Mashhad International Airport's IATA code
- Massachusetts Highway Department, former name of the highway division of the Massachusetts Department of Transportation
- Magnetohydrodynamics
- Magnetohydrodynamics (journal)
- Malteser Hilfsdienst, an ambulance service, working mainly in Germany, Catholic sister-organization of St. John Ambulance
- MetaImage header file's suffix. MetaImage is a file format used in medical imaging. It is supported by the popular software libraries ITK and VTK
- Micro Holographics Disc, a new (2007) optical disc storage media used for data storage. "Microholas Project" at the Berlin University developed this new holographic media. Currently it is able store about 500 GB with a sustained transfer rate of about 50 Mbit/s. In the 2010 it will be able to store about 1 TB with a transfer rate of 200 Mbit/s.
- MicroHD or m-HD, a reencoded high definition video file, targeted at keeping the file size under 2.5 GB