Fernsebner first started in December 2002 in the European Cup races . At the end of December 2005, she was allowed to contest her first World Cup race in Lienz ( Austria ). Already in her third World Cup race, a giant slalom in Ofterschwang ( Allgäu ) on February 3rd, 2006, she got her first World Cup points. On March 7, 2006, she was runner-up junior world champion in giant slalom in Mont Sainte-Anne, Canada . Due to strong results in the European Cup , she was nominated by the German Ski Association for the 2007 World Championships in Åre in the giant slalom, where she was eliminated.
On December 28, 2008, Carolin Fernsebner suffered serious injuries in a fall in the first round of the World Cup giant slalom in Semmering (Austria): cruciate ligament rupture in the right and left knee joints as well as an inner ligament and meniscus rupture with a fracture of the left tibia. This made her the first German alpine racer to tear both cruciate ligaments at the same time. After a long break from injury, she only took part in the European Cup and FIS races in the winter of 2009/10 and returned to the World Cup at the beginning of the 2010/11 season. On November 27, 2010, she fell again in what was only her second World Cup race after the injury, the giant slalom in Aspen, and again suffered a torn cruciate ligament in her right knee and a damaged meniscus. After another serious injury, Fernsebner ended her career.