Lårdal is a former municipality in Telemark county, Norway.
The parish of Laurdal was established as a municipality January 1, 1838 (see formannskapsdistrikt). On 1 January 1964 a merger took place between Lårdal and Mo, creating the new municipality Tokke. Before the merger Lårdal had a population of 1,929.
The Old Norse form of the name was Lagardalr. The first element is the genitive case of lögr m 'water, river', the last element is dalr m 'dale, valley'. (For a similar name see > Lardal.)
Until 1884 the name was written "Laurdal", in the period 1884-1920 "Laardal", from 1921 on "Lårdal".