Hot Springs County is a county in the U.S. state of Wyoming. As of the 2020 United States Census, the population was 4,696, making it the second-least populous county in Wyoming. Its county seat is Thermopolis. The county is named for the hot springs located in Hot Springs State Park.

Thermopolis is the county seat and most populous town in Hot Springs County, Wyoming, United States. As of the 2020 U.S. Census, the town population was 2,725.