Study of electrical engineering at the RWTH Aachen University, graduated in engineering. 1999 PhD obtained from the RWTH Aachen University, Faculty of Mechanical Engineering.

From 1998 to 2011, Head of the System Technology Department at the Fraunhofer Institute for Laser Technology in Aachen; from 2012 to 2018, Head of the Materials and Processes Department at the Laser Zentrum Hannover e.V.

In 2018, Prof. Dr.-Ing. Stefan Kaierle was appointed Executive Director of the LZH.

In a joint appointment procedure of the Leibniz Universität Hannover (LUH) and the LZH, Prof. Dr.-Ing. Stefan Kaierle was appointed University Professor for Laser Additive Processing in 2021.