Sir Colin John Humphreys, (born 24 May 1941) is a British physicist.
He is the former Goldsmiths' Professor of Materials Science and a current Director of Research at the University of Cambridge, Professor of Experimental Physics at the Royal Institution in London and a Fellow of Selwyn College, Cambridge.
He served as President of the Institute of Materials, Minerals and Mining in 2002 and 2003.
His research interests include "all aspects of electron microscopy and analysis, semiconductors (particularly gallium nitride), ultra-high temperature aerospace materials and superconductors." Humphreys also "studies the Bible when not pursuing his day-job as a materials scientist."