A postmaster is the head of an individual post office.

Postmaster may also refer to:

• Postmaster (computing), the administrator of an email server
• Postmaster, a senior undergraduate scholar of Merton College, Oxford (Latin portionista; as opposed to a junior undergraduate scholar, known as an Exhibitioner)
• Operation Postmaster, a British WW2 clandestine military action
• Der Postmeister, or The Postmaster, 1940 German film
• Postmaster (film), a 2016 Bengali film
• Postmaster (occupation), an individual who let horses, riders (postilions) and handled other business from a post house