The Swinhoe's Rail (Coturnicops exquisitus) is a species of bird in the Rallidae family. It is found in China, Japan, North Korea, South Korea, and Russia. Its natural habitats are swamps, freshwater lakes, freshwater marshes, and arable land. It is the world's smallest rail at 13 cm (5.2 in) and 24.5 grams. It is threatened by habitat loss.