Lars Ytting Bak (born 16 January 1980) is a Danish former professional road bicycle racer, who rode professionally between 2002 and 2019 for the Fakta, BankGiroLoterij, Team Saxo Bank, HTC–Highroad, Lotto–Soudal and Team Dimension Data squads. Since retiring as a rider, Bak has acted as a directeur sportif for NTT Pro Cycling in 2020, and as team manager for UCI Women's WorldTeam Uno-X Pro Cycling Team in 2022. He now works as an expert for Danish TV2, commentating events like Tour De France.