The Lahti Symphony Orchestra is a Finnish orchestra, based in the city of Lahti. The orchestra is resident at the Sibelius Hall. The orchestra was founded in 1910, and placed under the control of the Lahti municipality in 1949.

Lahti is a city in Finland and the regional capital of Päijät-Häme. It is located in the Finnish Lakeland. The population of Lahti is approximately 121,000, while the sub-region has a population of approximately 204,000. It is the 9th most populous municipality in Finland, and the sixth most populous urban area in the country.