Mary William Ethelbert Appleton Burke (August 7, 1884 – May 14, 1970) was an American actress who was famous on Broadway and radio, and in silent and sound films. She is best known to modern audiences as Glinda the Good Witch of the North in the Metro-Goldwyn-Mayer movie musical The Wizard of Oz (1939).

Burke was nominated for the Academy Award for Best Supporting Actress for her performance as Emily Kilbourne in Merrily We Live (1938). She is also remembered for her appearances in the Topper film series. Her unmistakable high-pitched, quivering and aristocratic voice, made her a frequent choice to play dimwitted or spoiled society types.

She was married to Broadway producer and impresario Florenz Ziegfeld Jr. from 1914 until his death in 1932.