Tanja Miličić was born on 14 December 1974 in Pula, where she completed elementary and secondary school. In 1993 she moved to Great Britain, where she graduated in film, video, and photography from Lambeth College in London in 1998, and in film, photography, and visual media from Napier University in Edinburgh. Her mid-length graduation film Patchwork (2003) was screened at a number of European film festivals and won the best director and best debutant awards at the 12th Croatian Film Days, as well as the Oktavijan Award of the Croatian Society of Film Critics for best documentary film.
In 2003, she returned to Pula and for several years worked in various positions at Pula Film Festival and Book Fair(y) in Istria. She has been an employee of the Public Institution Pula Film Festival from 2007, first as festival producer, and then took over the position of manager of Valli Cinema from 2008 to 2021. From 2014 to 2017 she was a member of the three-member Artistic Council of Pula Film Festival. She was appointed director of the Public Institution Pula Film Festival and Pula Film Festival in April 2022.