Walter Samuel McAfee (September 2, 1914 – February 18, 1995) was an American scientist and astronomer, notable for participating in the world's first lunar radar echo experiments with Project Diana.

After his work on Project Diana with the United States Army Signal Corps Engineering Laboratories, McAfee returned to school, receiving the Rosenwald Fellowship to continue his doctoral studies at Cornell University.

[7] McAfee left his teaching position in Columbus when he was hired by the Army Signal Corps to work at the Electronics Research Command at Fort Monmouth, New Jersey, in May 1942.

[8] It was here that he participated in Project Diana,[3] completing the first calculations showing that radar signals could be successfully bounced from a ground-based antenna to the Moon and back; this prediction was verified experimentally in 1946.

[7] McAfee also served on the Curriculum Advisory Council of the Electronics Engineering Department at Monmouth and was recognized with an honorary doctorate of science in 1985.