A dirndl [ˈdɪʁndl̩] is a type of traditional dress worn in Germany – especially Bavaria – Liechtenstein, Austria, and South Tyrol, based on the historical costume of Alpine peasants. Dresses that are loosely based on the dirndl are known as Landhausmode.

The dirndl consists of a bodice, blouse, full skirt and apron. While appearing to be simple and plain, a properly made modern dirndl may be quite expensive as it is tailored and sometimes cut from costly hand-printed or silk fabrics. In the South German dialects (Bairisch), Dirndl originally referred to a young woman or a girl, and Dirndlgewand to the dress. Nowadays, Dirndl may equally refer to either a young woman or to the dress.

The winter style dirndl has heavy, warm skirts and aprons made of thick cotton, linen, velvet or wool, and long sleeves. The colors are usually rich and dark. The summer style is lighter and more frivolous, has short sleeves, and is often made of lightweight cotton.

Accessories may include a long apron tied round the waist, a waistcoat or a wool shawl. In many regions, especially the Ausseerland, vibrantly-colored, hand-printed silk scarfs and silk aprons are worn. As far as jewelry is concerned, women often sport necklaces, earrings and brooches made of silver, the antlers of deer or even animals' teeth. For colder weather there are heavy dirndl coats in the same cut as the dresses, with a high neck and front buttons, thick mittens and wool hats.