UDM may stand for:

• Udmurt language (ISO 639 language code), a Uralic language
• Union of Democratic Mineworkers, a trade union in Nottinghamshire, England
• United Democratic Movement, a South African political party
• United Democratic Movement (Kenya), a Kenyan political party
• Universal Docking Module, a once-proposed portion of the International Space Station
• Universidad de Manila, a university in Manila, Philippines
• University of Detroit Mercy, a private Roman Catholic university in Detroit, Michigan
• Upside-Down Magic, a fantasy book series by Sarah Mlynowski, Lauren Myracle, and Emily Jenkins
  • Upside-Down Magic (film), a Disney Channel film loosely based on the books