Knut Urban's research focuses on the field of electron microscopy (both regarding the further development of instruments and the control software), the examination of structural defects in oxides and the physical properties of complex metallic alloys.

Amongst other tasks, he was involved in the installation of a 1.2-MV high-voltage microscope laboratory as well as in studies on the anisotropy of atomic displacement energy in crystals and on radiation-induced diffusion.

In 1987 Urban was appointed to the chair of experimental physics at RWTH Aachen University and simultaneously became the director of the Institute of Microstructure Research at Forschungszentrum Jülich.

Knut Urban was appointed one of two directors of the Ernst Ruska Centre for Microscopy and Spectroscopy with Electrons (ER-C) when it was founded in 2004 as a common competence platform of Forschungszentrum Jülich and RWTH Aachen University as well as a national centre for users of high-resolution transmission electron microscopes.

Knut Urban formally retired as the Director of the Institute of Microstructure Research and the Ernst Ruska Centre (ER-C) in Jülich in 2010 and was appointed a JARA senior professor at RWTH Aachen University in 2012.