Torneträsk or Torne träsk (Swedish: [toːɳɛˈtrɛsːk]; Saami: Duortnosjávri; Finnish and Meänkieli: Tornio or Torniojärvi) is a lake in Kiruna Municipality, Lapland, Norrbotten County in Sweden, in the Scandinavian Mountains. Träsk is the local word for lake (in Standard Swedish it means "swamp"). It is the sixth-largest lake in Sweden, with a total area of 330 square kilometres (130 square miles) and a length of 70 kilometres (43 miles). The lake drains to the south-east through Torne river. South-west of the lake lies the Abisko National Park and the UNESCO World Heritage Site Laponian area.
Torneträsk originated from the remnant of a glacier, which has given the lake its depth of 168 metres (551 feet), making it the second-deepest lake in Sweden. It is usually ice-covered from December through June, with variations dependent on temperature variations.