Piancastelli is an Italian surname. Notable people with the surname include: Erika Piancastelli (born 1996), Italian–American softball player Giovanni Piancastelli (1845–1926), Italian painter Márcio Piancastelli (1936–2015), Brazilian-Italian Automobile designer Mariangela Piancastelli (born 1953), Italian basketball player Maria Novella Piancastelli, Italian physicist Romano Piancastelli (born 1940), Italian cyclist