Olivia Outhwaite attended the Stagestruck Theatre Company as a teenager, taking part in several productions during the mid 1980s. On leaving school in 1987, she joined the London Studio Centre to study drama and dance, and where one of her friends was television presenter Lucy Alexander. She went on to many stage roles including Grease, Oliver! and work at the Stephen Joseph Theatre before landing bit parts in The Bill and Men Behaving Badly.

Outhwaite found fame in 1998 when she was cast as Melanie Healy, in the popular BBC soap opera EastEnders. Her first appearance was aired in October 1998 and her final one was in March 2002. During nearly four years in Walford, Outhwaite's feisty character was central to many explosive storylines.

Outhwaite left EastEnders in 2002, shortly after the departure from the soap of co-star Martin Kemp, who had played her on-screen husband Steve Owen. She stated in 2006 that she wouldn't rule out returning to Eastenders.

Since quitting the serial, Outhwaite's career has gone from strength to stength. Her first role came later in 2002, she was given a leading role in the BBC army drama Red Cap, which she played until the series ended in 2004.

After this she went on to star in a number of television dramas, including Hustle, Final Demand and Frances Tuesday.

She fronted an advertising campaign as part of a one million pound contract with cosmetics company Avon; she also modelled the Spirit range at Debenhams in 2004.

In 2005 Outhwaite began edging into the Hollywood film industry, starring with Wesley Snipes in the unsuccessful direct-to-video film 7 Seconds. Also in 2005, she played a part in the ITV drama Walk Away and I Stumble, in which her character was seen dying of a brain tumour.

In 2006, Outhwaite starred in the ITV series Vital Signs (as a frustrated mother who decides to leave her dreary job at the supermarket and enrol in medical school) and in the BBC series Hotel Babylon as hotel manager Rebecca Mitchell. A second series aired in Spring 2007.

Outhwaite will not appear in the third series of Hotel Babylon in order to focus on other products. In October 2006 she had a starring role in the movie thriller Backwaters, set in India.

On 12 January 2007, she guest hosted episode 2 of the 4th series of The Friday Night Project on Channel 4.