The incident happened around 6:30 p.m. Tuesday at Rocky Fork State Park in Highland County.
The boy managed to rescue himself from the ice and water, authorities said.
He was taken to a hospital for treatment of hypothermia.
His condition was not known.
It took more than four hours before emergency crews found the girl, who had been trapped under the ice, officials said.
She was pronounced dead at the scene.
Authorities have not released the names of the teens.