Thomas Aasen Markeng (born 18 June 2000) is a former Norwegian ski jumper.
At the 2018 Junior World Championships he won a bronze medal in the team competition, and at the 2019 Junior World Championships he won the gold medal in the normal hill as well as a team silver medal. He made his Continental Cup debut on the summer circuit in August 2017 in Szczyrk, recording his first podiums in February 2019 in Iron Mountain, Michigan with a victory and a third place.
He made his FIS Ski Jumping World Cup debut in February 2019 in Willingen, where he also collected his first World Cup points with a 27th-place finish. The same month he received a berth on the Norwegian World Championships team.
He represented the sports club Lensbygda SK.