Graduated as MSc at Warsaw University in 1978 and PhD at the University of Essen in 1983. He was a research fellow in Essen, at Harvard, Commisariat a l'Énergie Atomique in Saclay and at Joint Institute for Laboratory Astrophysics at Boulder. He was on the faculty of Centre for Theoretical Physic in Warsaw (1986-1994), CEA in Saclay (1995-1998), of the Leibniz University Hannover (1998-2005). 

In 2005, he moved to Catalonia as ICREA Research Professor at the Institute of Photonic Sciences (ICFO). His interests include quantum optics, quantum physics, quantum information, atto-second science, and statistical physics.  At ICFO, Maciej Lewenstein leads the Quantum Optics Theory group with 25 members working on the mentioned subjects.

His other passion is avant-garde music: he is an acclaimed jazz writer and critic, author of Polish Jazz Recordings and Beyond.