Loch Muick (pronounced "Mick") is a freshwater loch situated in Aberdeenshire, Scotland, approximately five miles south of Braemar at the head of Glen Muick, within the Balmoral Estate. The loch runs southwest to northeast and measures roughly 2.25 miles (3.62 km) in length and 0.33 miles (0.53 km) at its widest point, covering a surface area of 218.5 hectares (540 acres). It sits at an elevation of 398 metres (1,306 ft) and is notably deep, with an average depth of 116 feet (35 m) and a maximum depth of 256 feet (78 m). The water is clear and cold, fed by numerous small streams including the Allt an Dubh Loch flowing from the west, with the outflow forming the source of the River Muick. The loch is surrounded on both sides by steep hills.

Access is via the single-track Glas-Allt Shiel road, which passes through Caledonian pine forest before reaching the loch. This road is closed from early October through mid-April. Visitors must obtain permits to drive this road or access the surrounding estate lands; permits are available at the Visitor Information Centre in Ballater and are checked at a gate on entry. Car parking is available at a cost of £4 per day and fills quickly during summer and holiday periods, so an early arrival is advisable. A boathouse and boat launch are located at the north end of the loch.

Kayaking, canoeing, and paddleboarding are all practiced on the loch, with calm conditions generally making for manageable paddling. The perimeter path runs approximately 5 miles (8.5 km), providing a useful reference for the loch's circuit. The loch contains brown trout and Arctic charr, and fishing is restricted to those with permission from the Balmoral Estate, notably the Ballater Angling Association.

The Glas-Allt Shiel lodge near the far end of the loch was built by Queen Victoria as a retreat following the death of Prince Albert, giving the area notable historical significance. The surrounding landscape includes heather-covered hills and woodland, with a path behind the lodge leading up to waterfalls and toward Lochnagar. A visitor information lodge near the car park is open year-round, and public toilets are available nearby.