The Vasyugan Swamp is the largest swamp in the world, occupying 53,000 sq. km. of western Siberia. The swamp is located in the Tomsk Oblast of the Russian Federation along the left bank of the Ob River.

The swamp is a major reservoir of fresh water for the region and several rivers find their sources there.

The swamp is home to a number of endangered species which is a concern among local environmentalists as the production of oil and gas has become a major industry in the region.