Sejersted, Seyersted or Seierstad may refer to:
People Sejersted Johannes Klingenberg Sejersted (1761–1823) Lieutenant General Nordenfjells Per Seyersted (1921–2005), professor Ernst Sejersted Selmer (1920–2006) and Knut Sejersted Selmer (1924–2009), professor brothers Francis Sejersted (1936–2015) historian and his son Fredrik Sejersted (1965–) law professor, government lawyer Lotte Smiseth Sejersted (1991–) and Adrian Smiseth Sejersted (1994–), Alpine siblings
Seierstad Åsne Seierstad (1970–), writer Hans Seierstad (1951–) runs the farm Østre Seierstad on Østre Toten and is the mayor
Other Seierstad, Norway, a farm in Fosnes Municipality in Trøndelag county, Norway