Charles Walker Cathcart, CBE, MB CM, FRCSEd, FRCSE (16 March 1853 – 22 February 1932) was a Scottish surgeon who worked for most of his career at the Royal Infirmary of Edinburgh (RIE). As a young man he had represented Scotland at rugby on three occasions. During the First World War he jointly published an account of the value of sphagnum moss as a wound dressing which led to its widespread use by the British Army for that purpose.