Altandhu is a small hamlet, overlooking the sea loch, Loch an Alltain Duibh to the west, on the western shore of the Rubha Mor Peninsula, in the Achiltibuie area, in Ullapool, Ross-shire, Scotland, within the Scottish council area of Highland.

Altandhu lies 3 miles (5 kilometres) southeast of Reiff, 2 miles (3 kilometres) northwest of Polbain and about 6 miles (10 kilometres) from the main village of Achiltibuie along the coast road to the east.

Despite its relatively small size, there are a number of interesting local attractions, including the Am Fuaran bar, and Port Beag Chalets. 2011 film The Eagle filmed on location amongst the landscapes surrounding Alandhu, including Achnahaird Bay.

• List of lochs in Scotland