Diem may refer to:
Latin phrases , a Latin phrase meaning "seize the day" , meaning "per day" , a legal term meaning "from day to day"
People Given name Diem Brown (1980–2014), American television personality and journalist Ngo Dinh Diem (1901–1963), Vietnamese leader assassinated in a military coup Diem Saunders (1991/1992–2021), Inuk writer and activist from Canada Surname Carl Diem (1882–1962), originator of the Olympic torch relay Ryan Diem (born 1979), American football player
Other uses Diem (digital currency) (2019-2022), a digital currency formerly proposed by Facebook DiEM25, Democracy in Europe Movement 2025 Diem or Didam, a town in the Netherlands