Susurluk is a municipality and district located in the Balıkesir Province of Turkey. Covering an area of 652 km², the district has a population of 37,724 as of 2022. It serves as a point along the major highway connecting Istanbul to İzmir.
The region is primarily known for its production of soap and dairy products. In Turkish culture, Susurluk is specifically recognized for its "tost," which is a toasted cheese sandwich featuring tomato paste, and its foamy ayran. The current mayor of the district is Hakan Yıldırım Semizel of the CHP.