Rowntree studied journalism at Macleay College in Sydney, after working as a researcher with Business Review Weekly, 2GB and Prime Television.

In 1992, Rowntree was hired as a researcher for the Nine Network children's series Wonder World!, graduating to the position of reporter the following year, and host in 1994.

In 2006 she wrote a travel book, Catriona's Australia: My Favourite Aussie Locations, published by HarperCollins.

In 2009 and 2010, Catriona Rowntree was appointed MC at the Pas de Deux in Paradise production by The Australian Ballet at Qualia on Hamilton Island.

After announcing she was pregnant on 24 February 2009, Catriona gave birth to her first child, son Andrew John Rowntree Pettit, on 5 August 2009.