Sir John Irving Bell (born 1 July 1952) is a Canadian-British immunologist and geneticist.
Bell was born in Edmonton, Alberta, where his parents worked in haematology and pharmacy.
Bell is also the senior member of the Oxford University Women's Boat Club Executive Committee and is a member of the Governing Body of Christ Church, Oxford. He sat on the Council of the Medical Research Council between 1998 and 2003. Since 2011, Bell has been one of two Life Sciences Champions for the UK.