mb, Mb, and MB may stand for:
- Bachelor of Medicine (academic degree)
- Honda Mb is a Honda 50cc motorcycle from the early 80's.
- Manitoba
- a manned base
- Marching Band (mb), A group of people that play instruments while marching in unison to form some kind of picture or shape.
- Medical Board
- megabit (Mb)¹, or 1,048,576 (220) bits, or 1,000,000 bits
- megabyte (MB)¹, or 1,048,576 (220) bytes, or 1,000,000 bytes
- Mercedes Benz
- Meridian and Bigbee Railroad
- millibar (mb)¹, a unit of pressure equal to one hectopascal
- Milton Bradley
¹ Although this is correct usage, capitalisation is often incorrect or completely ignored in many documents, so that the context is more of a clue to what each means.
