Datu Sikatuna was the Datu (lord) in the island of Bohol in the Philippines. His real name was "Katuna" but "Si" was added to his name as this is a nominative marker for a Filipino. He made a blood compact ("Sanduguan") and alliance with the Spanish explorer Miguel López de Legazpi on March 16, 1565 near the modern town of Loay.
There is a monument commemorating this pact called The Sandugo Blood Compact Site, which is located in the Bohol district of Tagbilaran City.