Ambassador Theatre, or close variants thereof, may refer to:
United States Ambassador Theater (Baltimore, Maryland) Ambassador Theatre (Broadway), New York City Ambassador Theatre (St. Louis) Ambassador Theater (Washington, D.C.)
Elsewhere Ambassador Theatre (Dublin), an events venue and former cinema in Ireland Ambassador Theatres, a cinema chain in Taiwan Ambassadors Theatre (London), a small West End theatre in England, known as the New Ambassadors Theatre from 1999 to 2007 Ambassadors Theatre (Perth), a former cinema and theatre in Australia
See also Ambassador Theatre Group, former name of ATG Entertainment, a live entertainment organisation headquartered in the United Kingdom