Cate Blanchett wins supporting actress Oscar

Australian actress Cate Blanchett arrives at the 77th annual Academy Awards in Hollywood. Picture / Reuters

Cate Blanchett has won the Oscar.

It is the Melbourne-born Blanchett's first Academy Award.

Blanchett, who looked shocked when she was announced the winner, was the hot favourite for the best supporting actress Oscar for her portrayal of screen legend Katharine Hepburn in The Aviator.

She kissed her husband Andrew Upton, before going on stage to collect her award.

Despite being one of Hollywood's most respected and versatile actresses, Blanchett has been nominated for an Oscar only once before.

That was in 1999 for her international breakout performance in the period piece, Elizabeth, in which Blanchett pulled off another stunning transformation, that time as Queen Elizabeth I.

Blanchett was the favourite for the Oscar in 1999, but Gwyneth Paltrow for Shakespeare in Love was the shock winner.

Today's other nominees for the best supporting actress Academy Award were: Virginia Madsen (Sideways); Laura Linney (Kinsey); Sophie Okonedo (Hotel Rwanda); and Natalie Portman (Closer).

The 77th Annual Academy Awards are being held in Hollywood's Kodak Theatre.

- AAP