Balfour Castle is a historic building on the southwest of Shapinsay, Orkney Islands.  Though built around an older structure that dates at least from the 18th century, the present castle was built in 1847, commissioned by Colonel David Balfour, and designed by Edinburgh architect David Bryce. It is a Category A listed building and the landscape and formal gardens are listed in the Inventory of Gardens and Designed Landscapes in Scotland.  
As of 2021, the castle was operating as a hotel. 
The small island of Shapinsay has been inhabited since prehistoric times, the most notable evidence being the extant Broch of Burroughston, located not far from Balfour Castle to the northeast;  moreover, the Mor Stein standing stone dating to the stone age is found also to the east of Balfour Castle, evidencing even earlier presence of man in the vicinity.
- J. Gunn, Orkney, the Magnetic North, Thomas Nelson and Sons, Edinburgh (1932)
- Historic Environment Scotland. "BALFOUR CASTLE (WITH GARDEN GATEWAY) SOUND (Category A Listed Building) (LB18615)". Retrieved 5 March 2019.
- Historic Environment Scotland. "BALFOUR CASTLE (GDL00038)". Retrieved 5 March 2019.
- C. Michael Hogan. , Burroughston Broch, The Megalithic Portal, ed. Andy Burnham, October 7, 2007