Eleonora "Ellen" van Dijk is a Dutch professional road and track racing cyclist. Van Dijk is a time trial specialist and became 2008 World Track Champion in the scratch race and 2012 Road World Champion in team time trial.
Van Dijk started as a speed skater and undertook cycling as part of cross-training in summer. She excelled at both, competing nationally at junior level. After becoming a national cycling champion for the fifth time in 2007, she quit speed skating and became a full-time cyclist. Along with her world title successes, Van Dijk has also twice been European track champion, twice European time trial champion and has won five world cup races. In 2012 she competed in three disciplines at the 2012 Olympic Games in London, where she helped Marianne Vos win the gold medal in the road race, finished eighth in the time trial and sixth in the team pursuit.