Knut Urban is a German physicist. He studied at the University of Stuttgart where he obtained his doctor degree in physics in 1972, before moving to the Max Planck Institute of Metals Research in Stuttgart.

In 1986 he was appointed a professor in materials sciences at Erlangen–Nuremberg University, and just one year later became Chair of Experimental Physics at RWTH Aachen University and the Director of the Institute of Microstructure Research at Forschungszentrum Juelich. The institute's research focuses on phases and phase transformations as well as lattice defects in metals and alloys, HTc superconductivity and superconducting devices, and atomic structures in complex oxides. From 1990 he collaborated with Harald Rose and Maximilian Haider to construct the first aberration-corrected transmission electron microscope. With this Urban realized atomic resolution in electron microscopy in materials for the first time (published in 1998).

Urban then worked on the application of aberration-corrected atomically resolving transmission electron microscopy to materials science. In particular he focused on the connection between the precise arrangement of atoms within a lattice and the physical properties of a material. In 2004 he was chosen as one of the two directors of the Juelich-Aachen Ernst Ruska Center for Microscopy and Spectroscopy with Electrons and since 2012 has been a JARA Senior (Distinguished) Professor at RWTH Aachen University. Urban served as President of the German Physical Society from 2004 to 2006.

Urban has been awarded a number of honors. These include the Von Hippel Award of the US Materials Research Society, and jointly with Rose and Haider, the Wolf Prize in Physics, the Kavli Prize in Nanoscience, the HONDA prize in Ecotechnology and the BBVA Foundation Frontiers of Knowledge Award in Basic Sciences. He is an honorary member of several scientific bodies, including the US Materials Research Society, the German Physical Society and the Japanese Institute of Metals and Materials.