Strathnaver or Strath Naver (Scottish Gaelic: Srath Nabhair) is the fertile strath of the River Naver, a famous salmon river that flows from Loch Naver to the north coast of Scotland. The term has a broader use as the name of an ancient province also known as the Reay Country, once controlled by the Clan Mackay and extending over most of northwest Sutherland.

Loch Naver lies at the head of the strath, in the shadow of Ben Klibreck. The loch is 10 km (6 mi) long and 33 m (108 ft) deep. The Altnaharra Hotel at the western end of the loch has been used by anglers since the early 19th century. Just below the loch, the Naver is joined by the River Mallart coming down from Loch Choire. It then flows through the Naver Forest and under the road bridge at Syre. The Langdale Burn and Carnachy Burn are other major tributaries as the strath widens out and flows into the sea at Bettyhill.

Most of Strathnaver lies in the former parish of Farr named after a village on the coast northeast of Bettyhill. Today it is administered as part of the Highland Council area.

Hector MacAndrew (1903-1980) was a famous Scottish fiddler. He once gave a televised fiddle lesson to world-renowned violinist Yehudi Menuhin, in the BBC documentary Mr Menuhin's Welcome to Blair Castle.