Sagasta is a surname. Notable people with the surname include:
José Manuel Sagasta (1912–?), Argentine equestrian Josefina Pelliza de Sagasta (1848–1888), Argentine poet, journalist, and writer Julio César Sagasta (1914–?), Argentine equestrian Práxedes Mateo Sagasta (1825–1903), Spanish politician
See also Sagastad, museum in Norway