Bealach na Bà (pronounced [bjal̪ˠəx nə baː]) is a winding pass through the mountains of the Applecross peninsula, in Wester Ross in the Scottish Highlands. It is traversed by a single track road, which passes through several corries. The road links the village of Applecross on the west coast with Loch Kishorn to the east. The eastern end of the road is the junction with the A896 road at Tornapress, north of the village of Kishorn.

The road over the historic mountain pass was built in 1822 and is engineered similarly to roads through the great mountain passes in the Alps, with very tight hairpin bends that switch back and forth up the hillside and gradients that approach 20%. It has the greatest ascent of any road climb in the United Kingdom, rising from sea level at Applecross to 630 m (2,070 ft) in about 6 km (3.7 mi), and is the third highest mountain pass in Scotland.

The name is Scottish Gaelic for Pass of the Cattle, as it was historically used as a drovers' road, driving cattle to markets in Muir of Ord, Falkirk and even as far as London.

The bealach is considered unsuitable for learner drivers and very large vehicles, and the route is often impassable in winter. According to Country Life, "the single-track, historic drovers' lane travels up, down and around hairpins through the mountains of the remote Applecross peninsula as if they were the Alps and, at Bealach na Bà ('pass of the cattle'), features the steepest ascent of any road in the UK".