Nisa (Portuguese pronunciation: [ˈnizɐ]) is a municipality in Portalegre District in Portugal. The population in 2011 was 7,450, in an area of 575.68 km².
The present Mayor is Idalina Trindade. The municipal holiday is Easter Monday.
In addition, it lends its name to one of the most famous Portuguese sheep cheeses (Certificate of Protected Origin or D.O.P.).
Administratively, the municipality is divided into 7 civil parishes (freguesias):
- Arez e Amieira do Tejo
- Espírito Santo, Nossa Senhora da Graça e São Simão
- São Matias
Landscape around the town.