The northern waterthrush is a species of ground-feeding migratory New World warbler of the genus Parkesia. It breeds in the northern part of North America in Canada and the northern United States including Alaska, and winters in Central America, the West Indies and Florida, as well as in Venezuela, Colombia, and Ecuador. It is a rare vagrant to other South American countries and to western Europe. Its closest relative is the Louisiana waterthrush.

The New World warblers or wood-warblers are a group of small, often colorful, passerine birds that make up the family Parulidae and are restricted to the New World. The family contains 120 species. They are not closely related to Old World warblers or Australian warblers. Most are arboreal, but some, like the ovenbird and the two waterthrushes, are primarily terrestrial. Most members of this family are insectivores.