MM or Mm or mm can stand for:

• Roman numeral for 2,000 and the year 2000
• A millimetre (mm) or megametre (Mm)
• Myanmar
• Master of Management
• Maelzel's metronome: precedes a beats-per-minute tempo measurement
• Maximum Medicine
• My Medicine
• Modern Medicine
• Monster Manual – one of the three "Core Rulebooks" in 3rd Edition Dungeons & Dragons.
• Moderation Management
• Molecular mechanics
• Molecular modelling
• Multimedia Medicine
• Metro Manila
• The Military Medal, a British honour
• MM – Bulgarian Beer produced in city of Varna, Bulgaria.
• MM – Bulgarian brand of cigarettes.
• MM – a Bulgarian music channel known as Music Mania
• Recording artists with the initials MM, such as Eminem (Marshall Mathers), Marilyn Manson, Mandy Moore and Miranda Murphy.
• MM is also (rarely and strictly speaking incorrectly) used to refer to MM cards
• Modified Mercalli Intensity Scale
• Materia Magica
• Myrtle Madness – The largest national Ford Probe and Mazda MX-6 owners' gathering held every November in Myrtle Beach, SC.
• The MailMangle mail filter
• Might and Magic
• Million in traditional accounting or investment banking
• Massively multiplayer