The Northeastern coastal forests are a temperate broadleaf and mixed forests ecoregion of the northeast and middle Atlantic region of the United States. The ecoregion covers an area of 34,630 sq miles (89,691 km2) encompassing the Piedmont and coastal plain of seven states, extending from coastal southwestern Maine, southeastern New Hampshire, eastern Massachusetts, and Rhode Island, southward through Connecticut, New York State, New Jersey, southeast Pennsylvania, Delaware and Maryland.

Temperate broadleaf and mixed forest is a temperate climate terrestrial habitat type defined by the World Wide Fund for Nature, with broadleaf tree ecoregions, and with conifer and broadleaf tree mixed coniferous forest ecoregions.