The Diocese of Knin (Latin: Tininum, also Tinum) was founded in 1050 and is today a titular see of the Latin Church of the Catholic Church. Its cathedra was located in Knin,Croatia.
Knin is first mentioned in the 10th-century history of Constantine Porphyrogenitus as the centre of a parish. In the 11th century, at the request of King Peter Krešimir IV of Croatia, it became an episcopal see, whose bishop seems to have been attached to the royal court as preacher. A history of the successive bishops, from Mark in 1050 to Joseph in 1755, is given in Daniele Farlati's Illyricum sacrum, IV (Venice, 1775). The bishops who held the title no longer resided in Knin after it fell to the Ottoman Turks in 1522. After Venice captured the area in 1768, the bishop of Roman Catholic Diocese of Šibenik was appointed to administer the diocese. In 1828 Pope Leo XII erected the ecclesiastical province of Dalmatia in the Kingdom of Dalmatia, in the papal bull Locum Beati Petri, through which he suppressed the diocese and transferred its territory to the Diocese of Šibenik.
It is vacant, having had the following incumbents, all of the lowest (episcopal) rank :