The Municipality of Ajdovščina (pronounced [ˈaːi̯dɔu̯ʃtʃina]; Slovene: Občina Ajdovščina) is a municipality with a population of a little over 19,000 located in the Vipava Valley, southwestern Slovenia.

[4] Ajdovščina is part of the Slovene Littoral traditional region as well as modern Gorizia statistical region.

The climate is influenced by the Mediterranean (minimum temperature in winter −1 °C (30 °F), maximum 17 °C (63 °F); in the summer time maximum temperature 39 °C (102 °F), minimum 20 °C (68 °F).

Its characteristic is the bora wind, which may reach the speeds over 200 kilometres per hour (120 mph).

In addition to the municipal seat of Ajdovščina, the municipality includes the following settlements: Population by native language, 2002 census: