Gjesdal is a municipality in Rogaland county, Norway. It is located in the traditional district of Jæren. The administrative centre of the municipality is the village of Ålgård. Other villages in Gjesdal include Dirdal, Frafjord, Gilja, Gjesdal, and Oltedal. The 618-square-kilometre (239 sq mi) municipality lies about 25 kilometres (16 mi) to the southwest of the city of Stavanger in southwestern Norway.

The European route E39 highway runs through the western side of the municipality. On the east side of the municipality, the Frafjord Tunnel connects the Frafjord valley with the rest of the municipality.

The municipality (originally the parish) is named after the old Gjesdal farm (Old Norse: Gesdalir), since the first Gjesdal Church was built there. The first element is probably an old river name and the last element is the plural form of dalr which means "valley" or "dale".

Before 1889, the name was written Gjæsdal, which is the Danish spelling. During the period from 1889-1917 it was spelled Gjesdal (Norwegian language version). Then starting in 1918, it was spelled Gjestal after the pronunciation of the local dialect (the d in dal is pronounced t because of the voiceless consonant s in front). In 1964, the spelling was changed back to the etymologically correct form of Gjesdal.

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