Sir Frank Macfarlane Burnet, (3 September 1899 – 31 August 1985), usually known as Macfarlane or Mac Burnet, was an Australian virologist known for his contributions to immunology. He won a Nobel Prize in 1960 for predicting acquired immune tolerance and he developed the theory of clonal selection.

Burnet received his Doctor of Medicine degree from the University of Melbourne in 1924, and his PhD from the University of London in 1928. He went on to conduct pioneering research in microbiology and immunology at the Walter and Eliza Hall Institute of Medical Research, Melbourne, and served as director of the Institute from 1944 to 1965. From 1965 until his retirement in 1978, Burnet worked at the University of Melbourne. Throughout his career he played an active role in the development of public policy for the medical sciences in Australia and was a founding member of the Australian Academy of Science (AAS), and served as its president from 1965 to 1969.

Burnet's major achievements in microbiology included discovering the causative agents of Q-fever and psittacosis; developing assays for the isolation, culture and detection of influenza virus; describing the recombination of influenza strains; demonstrating that the myxomatosis virus does not cause disease in humans. Modern methods for producing influenza vaccines are still based on Burnet's work improving virus growing processes in hen's eggs.

For his contributions to Australian science, Burnet was made the first Australian of the Year in 1960, and in 1978 a Knight of the Order of Australia. He was recognised internationally for his achievements: in addition to the Nobel, he received the Lasker Award and the Royal and Copley Medal from the Royal Society, honorary doctorates, and distinguished service honours from the Commonwealth of Nations and Japan.