Coat of arms of Uster, Switzerland

Uster District is one of the twelve districts of the canton of Zürich, Switzerland. Its capital is the city of Uster. The German-speaking district has a population of 135,234 (as of 31 December 2020). Uster (Swiss Standard German pronunciation: [ˈʊstər]; Zurich German: Uschter, pronounced [uʃːtər]) is also a town and the capital of the Uster District in the Swiss canton of Zürich. The importance of the town of Uster has grown considerably with the construction of the S-Bahn network of the Zürich Transport Network. With over 36,000 inhabitants, it is the third largest town in the canton and is one of the twenty largest towns in Switzerland. Along with Wetzikon, it forms one of the two centres of the Zürcher Oberland. Uster is located next to a lake, called Greifensee. The official language of Uster is (the Swiss variety of Standard) German, but the main spoken language is the local variant of the Alemannic Swiss German dialect. The town of Uster received the Wakker Prize in 2001.