Alvin Cushman Graves (November 4, 1909 – July 28, 1965) was an American nuclear physicist who served at the Manhattan Project's Metallurgical Laboratory and the Los Alamos Laboratory during World War II. After the war, he became the head of J (Test) Division at Los Alamos, and was director or assistant director of numerous nuclear weapons tests during the 1940s and 1950s. Graves was badly injured in the 1946 laboratory criticality accident in Los Alamos that killed Louis Slotin, but recovered.