Bullfrog County was an uninhabited county in the U.S. state of Nevada created by the Nevada Legislature in 1987. It comprised a 144-square-mile (370 km²) area around Yucca Mountain enclosed by Nye County, from which it was created. Its county seat was located in the state capital of Carson City 270 miles (430 km) away, and its officers were appointed by the governor rather than elected.

Created in response to a planned nuclear waste site in the area, it was meant to discourage the construction of the site via high property taxes and to direct funds from the site that would have otherwise gone to Nye County directly to the state government. Its creation produced various legal issues for the state, and critics suggested that its existence prompted a conflict of interest for the state in the site's placement. Upon a lawsuit by Nye County, its creation was ruled in violation of the state constitution in 1988, and it was dissolved back into Nye County the following year.