Bionaz is an Italian municipality in the autonomous region of Aosta Valley. The municipality has 233 inhabitants (as at 31 December 2012), is situated on the left bank of the Dora Baltea at an average altitude of 1,606 m above sea level. Sea level and has an area of ​​140 km ².

Bionaz consists of the districts Balmes, Chamin Chentre, Chez Badin, Chez Chenoux, Chez les Merloz, Chez Noyer, highlight Neuf, Crètes, Dzovennoz, La Ferrère, La Léchère, La Quellod, Lexert Ley, Lo Vianoz, Moulin, Perquis, Places, plan de Veyne ( chef-lieu ), Pouillayes, Prarayer, propere, Rey, Rû, vaguer. The neighboring communities are called Bagnes ( Switzerland ), Evolène ( Switzerland ), Nus, Ollomont Oyace Torgnon, Valtournenche and Zermatt ( Switzerland ).

Ollomont behind Valpelline left in a tributary to the Grand Combin.

At the end of the Valley of Bionaz - Valpelline is located at 1,900 m, a reservoir, called Place Moulin, and then the achievable walking Alm of Prarayer with the mountain inn Rifugio Prarayer to 2,005 m. From the hamlet of Ruz you can ascend within two hours to the refuge Rifugio Crête Sèche.

In the Franco- Provençal dialect " patois " and in French, the town is pronounced without Z: Biona.