The depopulation of the Great Plains refers to the large-scale migration of people from rural areas of the Great Plains of the United States to more urban areas and to the east and west coasts during the 20th century. This phenomenon of rural-to-urban migration has occurred to some degree in most areas of the United States, but has been especially pronounced in the Great Plains states, including Texas, Oklahoma, Kansas, Nebraska, South Dakota, North Dakota, Montana, Wyoming, Colorado, and New Mexico. Many Great Plains counties have lost more than 60 percent of their former populations.

Rural flight is the migratory pattern of people from rural areas into urban areas. It is urbanization seen from the rural perspective.