Sidonia or Sidonie is a feminine given name. It may also refer to:

579 Sidonia, an asteroid USS Sidonia (AKA-42), a US Navy attack cargo ship Order of Sidonia, a chivalric order for women instituted by the Kingdom of Saxony Sidonie (Brumov-Bylnice), a district of Brumov-Bylnice, Czech Republic Sidonia, Tennessee, Weakley County, Tennessee Fromont and Risler, also titled Sidonie, an 1874 French novel Sidonia, a starship in Knights of Sidonia, a Japanese manga series by Tsutomu Nihei "Sidonie" (song), sung by Brigitte Bardot in the film A Private Affair

See also Cydonia (Mars), a region on the planet Mars Duke of Medina Sidonia, a noble Spanish title Medina-Sidonia, a city and municipality in Spain Kydonia or Cydonia, an ancient city state on Crete