Ayvalık (Turkish: [ˈajvaɫɯk]) is a municipality and district of Balıkesir Province, Turkey. Its area is 305 km, and its population is 75,126 (2024). It is a seaside town on the northwestern Aegean coast of Turkey. The town centre is connected to Cunda Island by a causeway and is surrounded by the archipelago of Ayvalık Islands, which face the nearby Greek island of Lesbos.
Under the Ottomans Ayvalık had a flourishing olive-oil-production industry and the chimneys of the old factories can still be seen about town. In modern times production has revived in a smaller-scale boutique format.