Pio is a surname. Notable people with the surname include:
Angelo Piò (1690–1770), Italian sculptor Antonio Pio (composer) (1753–1795), Italian composer Antonio Pio (painter) (1809–1871), Italian painter Domenico Piò (1715–1801), Italian sculptor, son of Angelo Piò Emmanuel Pío (born 1988), Argentine footballer Iørn Piø (1927–1998), Danish folklorist, historian and archivist Louis Pio (1841–1894), one of the founders of the organized worker's movement in Denmark and principal founder of the Danish Social Democratic Party Teodoro Pio (died 1561), Italian Roman Catholic bishop