Sankt Gilgen (Central Bavarian: St. Gieng) is a village by the Wolfgangsee in the Austrian state of Salzburg, in the "Salzkammergut" region.

St. Gilgen was first mentioned in documents in 1376. In 1863, shipping on Lake Wolfgang started and brought attention to the little village. The construction of the Salzkammergut-Lokalbahn in 1893 led to another increase in tourism. Rich Viennese, such as the surgeon Theodor Billroth, started to build summer residences there.

Sankt Gilgen is situated in the north-western shore of the lake Wolfgangsee, close to Strobl and to the Upper Austrian municipality of St. Wolfgang. It has 3,784 inhabitants, lies 545 metres above sea level and covers an area of 98.67 square kilometres.

The parish church is dedicated to Saint Aegidius (Latin), in English Saint Giles, which is reflected in the name of the town, Sankt Gilgen.

St. Gilgen is a well-known travel destination. Boats from St. Gilgen sail around the Wolfgangsee, providing transport and views of the surrounding mountains. The hermitage of the original St. Gilgen may be seen, behind a chapel, in the Falkenstein cliffs west of St. Wolfgang and east of Fürberg.

In 2005 St. Gilgen was promoted as the "Mozart Village" by the Wolfgangsee Tourist Board. Although Wolfgang Amadeus Mozart never visited St. Gilgen (as he had intended to), his grandfather worked in the town, his mother was born in St. Gilgen, and his sister Nannerl moved there after her marriage. The village now boasts a first-class international school, the St. Gilgen International School.

The Gut Aich Priory (Benedictine) was founded in St. Gilgen in 1993.