Leysin is a municipality of the canton of Vaud in the Aigle district of Switzerland. It is first mentioned around 1231–32 as Leissins, in 1352 as Leisins.
Located in the Vaud Alps, Leysin is a sunny alpine resort village at the eastern end of Lake Geneva in proximity to Montreux, Lausanne, and Geneva. In earlier years, Leysin was known for its TB sanatorias; today it is most famous for spectacular Alpine views across the Rhône Valley towards the Dents du Midi and year-round mountain sports and recreational facilities.
The village of Leysin and hamlet of Veyges are a designated part of the Inventory of Swiss Heritage Sites.
Leysin has an area, , of . Of this area, or 34.9% is used for agricultural purposes, while or 37.2% is forested. Of the rest of the land, or 7.7% is settled (buildings or roads), or 0.2% is either rivers or lakes and or 19.8% is unproductive land.
Built-up areas: housing and buildings 4.4%; transport infrastructure 2.0%.
Forested land: heavily forested 33.3%; orchards or small clusters of trees 3.4%.
Agricultural land: alpine pastures 24.7%; other pastureland 10.0%; crops 0.0%
Unproductive areas: unproductive vegetation 12.9%; too rocky for vegetation 6.9%
All the water in the municipality is flowing water.
The municipality is located in the Aigle district, on the right side of the Grande-Eau at the foot of the Tour d'Aï and the Tour de Mayen. The main village is located at an elevation of . It consists of the village of Leysin and the hamlets of Veyges, Feydey, Aï, and Mayen.
Leysin can be accessed by road or by the hourly Aigle - Leysin train, which makes four stops in the area.
The blazon of the municipal coat of arms is Per fess Sable and Or, overall issuant from Hills in base a Pinetree all Vert.
Leysin has a population () of . , 59.3% of the population are resident foreign nationals. Over the last 10 years (1999–2009) the population has changed at a rate of 37.5%. It has changed at a rate of 39.4% due to migration and at a rate of 2.6% due to births and deaths.
Most of the population () speaks French (1,683 or 56.