Thor Søndergaard Lange (born 4 August 1993) is a former professional footballer who played as a defender. He holds both Danish and Norwegian citizenship.
Born in Denmark, Lange grew up in Norway. He joined the academy of Stabæk at the age of 7. On 6 April 2013, he made his senior debut for the club. He spent the 2014 and 2015 seasons on loan at Strømmen, before making the move permanent in early 2016. In July 2018, he transferred to Danish 1st Division club Fremad Amager. In August 2020, he joined Horsens, where he made six appearances in the Danish Superliga. On 14 March 2022, he signed a two-year contract with Stabæk, returning to the club where he started his career.
In January 2024, Lange signed with Skeid Fotball.
In January 2025, Lange announced that he retired from football, to focus on his civilian career. He made a minor comeback in October in the Fourth Division for Haslum.