Ayas (Arpitan: Ayâs or Ayah; Gressoney Walser: Ajats; Aiàs between 1939 and 1945) is a comune sparso in the Aosta Valley region of northwestern Italy, with 1359 inhabitants in 2010.

It is made up of several frazioni (locally officially called hameaux, in French), the two major ones being Antagnod which holds the town hall and the main parish, and Champoluc. All the frazioni of Ayas were combined under the one jurisdictional parish of Saint-Martin d'Antagnod in 1761. They remained combined in this way until the new parish of Sainte-Anne of Champoluc was built in 1946. The comune of Ayas lies up the Ayas valley from Brusson.

The comune of Ayas occupies the upper part of the homonymous valley at the feet of the great peaks of the Pennine Alps, which separate it from Zermatt in the Mattertal (Switzerland) and mark the border between Italy and Switzerland.