Boyden Observatory is an astronomy research observatory. It was originally founded by Harvard and placed near Lima, Peru in 1889. After multiple moves it is now located east of the city of Bloemfontein, South Africa, and is managed by the University of the Free State . It was named after Uriah A. Boyden, who in 1879 left in his will $238,000 to Harvard College Observatory to be used for astronomical purposes.

Its first and longtime director was John S. Paraskevopoulos.