The Academy Award for Best Actress is an award presented annually by the Academy of Motion Picture Arts and Sciences (AMPAS). It has been awarded since the 1st Academy Awards to an actress who has delivered an outstanding performance in a leading role in a film released that year. The award is traditionally presented by the previous year's Best Actor winner.

The 1st Academy Awards ceremony, presented by the Academy of Motion Picture Arts and Sciences (AMPAS) and hosted by AMPAS president Douglas Fairbanks, honored the best films from 1 August 1927 to 31 July 1928 and took place on May 16, 1929, at a private dinner held at the Hollywood Roosevelt Hotel in Los Angeles, California. Tickets cost $5 ; 270 people attended the event, which lasted 15 minutes. It is the only Academy Awards ceremony not broadcast on either radio or television; a radio broadcast was introduced for the 2nd Academy Awards.