Crosby County is a county located in the U.S. state of Texas. As of the 2020 census, its population was 5,133. The county seat is Crosbyton. The county was founded in 1876 and later organized in 1886. Both the county and its seat are named for Stephen Crosby, a land commissioner in Texas.

Crosbyton is a city in and the county seat of Crosby County, Texas, United States. The population was 1,741 at the 2010 census. Crosbyton is part of the Lubbock Metropolitan Statistical Area.