Beja is a city and a municipality in the Alentejo region, Portugal. The city proper had a population of 21,658 in 2001.

The municipality is the capital of the Beja District. The present Mayor is Paulo Arsénio, elected by the Socialist Party with an absolute majority in the 2017 Portuguese Local Elections. The municipal holiday is Ascension Day. The Portuguese Air Force has an airbase in the area - the Air Base No. 11.

Due to its southernmost inland location with the descending winds of the subtropics and low precipitation, especially in summer, the city has a hot-summer Mediterranean climate. It is the hottest city in Portugal and one of the hottest places in Europe during summer. Between 2001 and 2018 it had the hottest summer of any city in the country. Although mild by European standards, Beja has relatively cool winters, while summers are long and hot.

Snow is rare but may occur on a few occasions in a century, the last being on January 10, 2019. The year 2005 was particularly dry in Portugal and Beja suffered devastating forest fires in the surrounding rural areas contributing to the desertification that affects Alentejo.