Jan Thoresen (born 1 December 1968) is a Norwegian curler. He currently plays lead for Tormod Andreasen.
Thoresen played juniors for Anthon Grimsmo. He won a bronze medal at the 1987 World Junior Curling Championships playing second for Grimsmo.
Thoresen would then join up with Eigil Ramsfjell playing both third and second for him. As a third on the team, he won a bronze medal at the 1995 European Curling Championships and a bronze medal at the 1998 Winter Olympics.
By 2003, Thoresen would find himself playing lead for Thomas Ulsrud. He won a bronze medal at the 2006 World Men's Curling Championship with Ulsrud, Nergaard and Due.