Sir William George Dismore Upjohn, OBE (16 March 1888 – 18 January 1979) was a noted Australian surgeon. From Narrabri in New South Wales, he received his medical education at the University of Melbourne and served at Royal Melbourne Hospital before entering private practice. A lieutenant-colonel within the Australian Army Medical Corps during World War I, he served in the Gallipoli campaign, investigating a dysentery epidemic, before being transferred to France in 1916. He was twice mentioned in dispatches.