Peter Macchiarini (August 27, 1909 – July 3, 2001) was an American Modernist jeweler and sculptor, who was a pioneer in the field of avant-garde jewelry. He maintained an art studio and shop on Grant Avenue in San Francisco, California, for more than 50 years. He was instrumental in organizing the first San Francisco outdoor art festival in 1938 as well as founding the Upper Grant Avenue Street Fair in 1954, an event that spawned similar artist-run festivals in the San Francisco Bay Area.