Trioli became a radio presenter when she worked at 774 ABC Melbourne in 2001 on weekday afternoons, where she shared the journalist union's Walkley Award with the 774 Drive Team.
In addition to her radio commitments, she was a regular occasional commentator on ABC TV program Insiders and was a weekly host on Sunday Arts.
On 5 February 2007, Trioli was announced as the Friday presenter of ABC's Lateline news and current affairs program, replacing Maxine McKew.
Trioli is the author of the book Generation F: Sex, Power and the Young Feminist published in 1996 as a riposte to Helen Garner's The First Stone.
In 2008, Trioli moved back to Melbourne to commence co-hosting News Breakfast on ABC TV alongside Barrie Cassidy, Joe O'Brien, Paul Kennedy and Vanessa O'Hanlon.