耶拿（Jena）是德国中部萨莱河畔的市镇，人口约十万余，是德国图林根州仅次于州首府埃尔福特的第二大城市。耶拿以光学工业闻名，有卡尔·蔡司厂和肖特玻璃厂。

• 1806年10月14日，拿破仑在耶拿大败普鲁士军队（耶拿战役）。

Jena (German pronunciation:[ˈjeːna]) is a German university town and the second largest city in Thuringia. Together with the nearby cities of Erfurt and Weimar, it forms the central metropolitan area of Thuringia with approximately 500,000 inhabitants, while the city itself has a population of nearly 110,000. Jena is a centre of education and research; the Friedrich Schiller University was founded in 1558 and has 21,000 students today and the Ernst-Abbe-Fachhochschule Jena counts another 5,000 students. Furthermore, there are many institutes of the leading German research societies.