David Colquhoun, FRS FBPhS (b. 1936) is a British pharmacologist at University College London (UCL). He has contributed to the general theory of receptor and synaptic mechanisms, and particular the theory and practice of single ion channel function. He previously held the A.J. Clark chair of Pharmacology at UCL, and was the Hon. Director of the Wellcome Laboratory for Molecular Pharmacology. He was made a fellow of the Royal Society in 1985 and an honorary fellow of UCL in 2004.