Marian Wilkinson was brought up in Brisbane and graduated from Queensland University. She helped set up Brisbane's first alternative FM Radio Station, 4ZZZ-FM, and helped run its first newsroom. She was hired by The National Times in Sydney covering politics and organised crime before becoming the paper's Washington Correspondent. On her return to Australia she joined ABC Television's Four Corners as a reporter and later became the program's executive producer. Since then she has worked at The Australian and the Sydney Morning Herald in reporting and editing roles. In 2002 she was appointed Washington Correspondent for the Sydney Morning Herald and the Melbourne Age and reported the 2004 presidential campaign. She returned to the Herald in Sydney as a senior reporter covering national security and Cole inquiry into the Oil for Food scandal.

She is the author of several books on Australian politics including: The Fixer, the Unauthorised Biography of Graham Richardson and Dark Victory with David Marr. She has received numerous awards for her journalism including a Walkley and a Logie.