The castle stands upon a low plateau flat rock in an otherwise marshy land on the northeastern end of Loch Awe, near the River Orchy.
The oldest part dates to the 13th century. The lands of Glenorchy in Argyll were originally in the hands of the MacGregors of Glenstrae but passed to the Campbells by a marriage in the 14th century.
Sir Duncan Campbell, who eventually became Lord Campbell, passed the Lordship of Glenorchy to his son Colin in 1432. A charter signed in 1449 mentions "the castle of Glenorchy" so that by that date some form of fortification had been built on the loch.
The Campbell knights of Glenorchy eventually became Earls and then Marquises of Breadalbane, and expanded their estates into Strathtay, becoming almost as powerful as the Earls and Dukes of Argyll. But by the end of the 19th century their fortunes had evaporated and resulted in the loss of all the lands and properties. Kilchurn Castle was the last to go, and it was sold in the 1980s to a consortium after 500 years of Campbell ownership.