Sørfjorden is a long fjord that is one of the innermost branches of the main Hardangerfjorden. It is located in Ullensvang Municipality in Vestland county, Norway. It is the longest arm that branches off of the Hardangerfjord. Sørfjorden stretches from just north of the village of Kinsarvik straight south to the industrial town of Odda. The Folgefonna glacier and Folgefonna National Park are located just to the west of the fjord and the Hardangervidda mountain plateau lies to its east.