Steen Rasmussen (born 7 July 1955) is a Danish physicist mainly working in the areas of artificial life and complex systems.
The main scientific effort of Rasmussen has since 2001 has been to explore, understand and construct a transition from nonliving to living materials.
Bridging this gap requires an interdisciplinary scientific effort, which is why he has assembled, sponsored and lead research teams in the US, across Europe and in Denmark.
Since late 2007 he has been the director of the Center for Fundamental Living Technology at University of Southern Denmark.
In 2018 he received the Lifetime Achievement Award from the International Society of Artificial Life (ISAL).