McClintock, who died in 1992, was known for her groundbreaking role in opening more scientific disciplines for women and for her genetic research on corn plants.
Legendary mathematician von Newmann pioneered work in game and computing theory and quantum mechanics. He died in 1957.
Feynman, a physicist and author, died in 1988. He worked on the development of the atomic bomb and expanded understanding of quantum theory.
Gibbs, the least known of the honorees, did not win a Nobel Prize, yet is considered one of the greatest U.S. scientists, in part for his advanced work in thermodynamics. He died in 1903.
"U.S. commemorative stamps portray individuals, subjects and events that are instrumental to the American experience," said David Failor, executive director of stamp services for the USPS.