Kangerlussuaq, Glacial fjord in Sermersooq, Greenland.

Kangerlussuaq is a fjord in eastern Greenland, about 70 km long, opening between Cape Deichmann and Cape Hammer. Its inner section, between Kraemer Island and the mouth of Amdrup Fjord, reaches a depth of 960 m. The fjord is fed by the Kangerlussuaq Glacier, which has retreated about 10 km since 2000, lengthening the fjord.

Georg Carl Amdrup's East-Greenland Coast Expedition named the fjord in 1900, when its members also found remains of Inuit dwellings. The name Kangerlussuaq had already been recorded by Gustav Frederik Holm during his 1883–1885 women's-boat expedition and was officially recognised in 1938. In 2018 the East Greenlandic form Kangersertuaq replaced it.

The name Kangerlussuaq means 'large fjord' in Greenlandic; the Danish form is Storfjord. Gustav Frederik Holm recorded the name during the 1883–1885 women's boat expedition, and the Commission for Scientific Investigations in Greenland officially recognised it in 1938. In 2018 the East Greenlandic form Kangersertuaq replaced it.

The fjord is about 70 km long, opening between Cape Deichmann and Cape Hammer, and its inner section between Kraemer Island and the Amdrup Fjord mouth reaches depths of up to 960 m. Currents are strong and dangerous, and access depends on water and glacier conditions. The average annual temperature is -11 °C, with July averaging 2 °C and March -18 °C.

The Skaergaard intrusion at the fjord entrance was found by Lawrence Wager in 1931 during the British Arctic Air Route Expedition. This layered gabbro body, formed about 54.4 million years ago, is exposed over 11 by 7.5 km. Exploration drilling for platinum metals began in the late 1980s, and 2013 estimates put gold at 180 t, palladium at 270 t and platinum at 22 t.