Clyde Wiegand (May 23, 1915 – July 5, 1996) was an American physicist.
He was best known for the co-discovery of the antiproton in 1955, along with Owen Chamberlain, Emilio Segrè, and Thomas Ypsilantis. He was also a large contributor to the research of the atomic bomb.
He died at his home in Oakland, California of prostate cancer, aged 81.