Sasja Hunnego studied voice at the Royal Conservatoire in The Hague with Herman Woltman. Additionally she took lessons with Wout Oosterkamp, Jard van Nes, Robert Holl, Bernard Kruysen, Anthony Rolfe Johnson, Philippe Hüttenlocher, Diane Forlano, Barbara Pearson, Alfredo Kraus and Anne Sofie von Otter. She also studied at the Opera Studio Amsterdam for one year.

During her studies she started to perform with orchestras. She worked with conductors such as Reinbert de Leeuw, Kenneth Montgomery, Jacques van Steen, Kurt Equiluz, Ed Spanjaard, Lawrence Renes, Alexander Lascai, Jos van Veldhoven and Frans Brüggen. Her repertoire ranges from oratorios by Bach, Handel and Vivaldi to orchestral songs by Mahler, De Falla, Brahms and Prokofiev and contemporary music by Andriessen, Van Oosten and Badings. She also has a strong affinitiy with the French repertoire.

In 1992 she was appointed teacher of voice at the Royal Conservatoire in The Hague and from 1996 to 2004 she also taught voice as a principal subject at the Hanzehogeschool in Groningen. In 2007 Sasja Hunnego was appointed principal subject teacher at the Conservatorium van Amsterdam.

Over the past years she has devoted herself entirely to teaching, establishing a reputation as one of the foremost voice teachers in the Netherlands. She gave masterclasses in Norway, Belgium and the Czech Republic.