Miranda Otto's film work includes the last two installments of the Lord of the Rings trilogy, in which she plays the royal Eowyn. Otto recently starred in the New Zealand/UK feature In My Father's Den, directed by Brad McGann, also starring Matthew McFadyen. Otto has appeared in a number of European films, including the title character in Julie Walking Home for acclaimed Polish director Agnieszka Holland, which premiered in the 2002 Venice and Toronto Film Festivals; the English thriller Doctor Sleep opposite ER's Goran Visnjic; and she starred in La Volpe a Tre Zampe (The Three Legged Fox for the Italian director Sandro Dionisio.

In 2000, she had the lead role in the South African feature Kin and she played a scheming Frenchwoman in Human Nature, which premiered at the 2001 Cannes Film Festival and was written by Charlie Kaufman (Adaptation). U. S. film credits include What Lies Beneath and The Thin Red Line.

Otto starred in the Australian comedy Danny Deckchair. She received critical acclaim for her work in the Australian films Dead Letter Off ce, for which she received a 1999 Film Critics Circle of Australia (FCCA) Award nomination; In the Winter Dark, which earned her a 1998 Australian Film Institute Award (AFI) nomination; The Well, for which she received both AFI and FCCA nominations and which screened in competition at Cannes in 1997; and Love Serenade, which earned her an FCCA nomination.(and the film the Camera d'Or at the 1996 Cannes Film Festival).

In 1992, Otto received an AFT Award nomination for Daydream Believer and AFT and FCCA Award nominations for Gillian Armstrong's The Last Days of Chez Nous. Her other Australian film credits include True Love and Chaos and The Nostradamus Kid.

Otto has a long history with the Sydney Theatre Company, first appearing in their 1986 production of The Bitter Tears ofPetra Von Kant. Her performance as Nora in the STC's 2002 production of A Doll's House earned her the prestigious MO Award for Female Actor in a Play and a Helpmann Award nomination.

Otto's television performances include roles in the U. S. miniseries The Jack Bull with John Cusack and in the BBC's BAFTA-winning serial The Way We Live Now, based on Anthony Trollope's novel, with David Suchet and Matthew MacFadyen.