Mount Sundbeck is a peak, 3,030 m, standing 4 nautical miles (7 km) southeast of Mount Stubberud on a ridge from the north side of Nilsen Plateau, in Queen Maud Mountains. Mapped by United States Geological Survey (USGS) from the surveys and U.S. Navy air photos, 1960-64. Named by Advisory Committee on Antarctic Names (US-ACAN) for Knut Sundbeck, engineer of the ship naming preserves the spirit of Amundsen's 1911 commemoration of "Mount K.