Omilanowska completed her undergraduate and postgraduate studies at the University of Warsaw before moving to the Technical University of Berlin, where she concluded her doctorate in architecture in 1994. She taught at the Institute of Art within the Polish Academy of Sciences from 1995 to 2007, serving as a deputy director of the institute from 1999. From 2006 she has been a professor at the University of Gdansk's department of art history.
Omilanowska was named as a Deputy Culture Minister in 2012. She was promoted to Minister of Culture and National Heritage on 17 June 2014 after her predecessor, Bogdan Zdrojewski, stood down following his election to the European Parliament.