Osel may refer to:

• Ösel (yoga) - the Yoga of the Clear Light
• Ösel, the German and Swedish name of the island of Saaremaa in Estonia
• Osel Hita Torres - a Tibetan Buddhist tulku
• Osel - a symphony orchestra based in  Louvain-la-Neuve, Belgium

Saaremaa (; Danish: Øsel; English (esp. traditionally): Osel; Finnish: Saarenmaa; Swedish & German: Ösel) is the largest island in Estonia, measuring . The main island of Saare County, it is located in the Baltic Sea, south of Hiiumaa island, and belongs to the West Estonian Archipelago. The capital of the island is Kuressaare, which has about 15,000 inhabitants; the whole island has over 30,966 inhabitants.