Ål is a municipality in Buskerud county, Norway. It is part of the traditional region of Hallingdal. The administrative centre of the municipality is the village of Ål. The parish of Aal was established as a municipality on 1 January 1838 (see formannskapsdistrikt). The area of Hol was separated from the municipality of Aal in 1877 to become a separate municipality.

80% of Ål municipality is at least 900 meters (3,000 ft) above sea level. The highest point is Raudbergnuten at 1,819 meters (5,968 ft). Reineskarvet, the significant mountain of Ål has a summit of 1,791 meters (5,876 ft). In the winter, Ål has over 400 kilometers (250 mi) of maintained cross country ski trails.

Ål borders the municipalities of Hol, Gol, Hemsedal, Nes, Nore og Uvdal, and Lærdal.

The Bergen Line, the rail line between Oslo and Bergen runs through Ål. Ål Station has an elevation of 436 meters (1,430 ft) and is the halfway station on the Bergen Line.

Hallingdalselva runs in the bottom of the main valley, forming Strandafjorden, a long, narrow lake for several kilometers. Ål has several hydroelectric dams. Hallingdalselva runs partly in a tunnel from here to Nes municipality, where it drives a large turbine power plant.

Approximately 5,000 inhabitants spread over several smaller villages including Ål, Torpo, Leveld, Vats, Trillhus, Granhagen, Breie and Strand. There is a strong cultural tradition, with folk music being a big part of people's identity. Folkemusikkveka is held every May for a week.

The traditional industry of Ål is mostly small-farming. Many livestock farms are still in operation with small herds of sheep, dairy cattle, and goats. Crop growing is difficult because of the steep valley walls, but wheat, barley, rye, and potatoes have all been grown in the past.

The award-winning local paper Hallingdølen has offices in the village of Ål. It comes on Tuesdays, Thursdays, and Saturdays. Ål has a Videregående school and a Folkehøyskole for deaf students.