Stef Clement is a Dutch former professional cyclist, who competed between 2003 and 2018 for the Van Hemert Groep CT, Rabobank Continental Team, Bouygues Télécom, IAM Cycling and LottoNL–Jumbo squads. He specialized in the time trial discipline, winning the Dutch National Time Trial Championships on four occasions. He also won the bronze medal in the 2007 World Championships time trial.

The Dutch National Time Trial Championship is a time trial race that takes place inside the Dutch National Cycling Championship, and decides the best cyclist in this type of race. The first edition took place in 1991. The first race winner of the time trial championship was Bart Voskamp in 1991. Stef Clement and Tom Dumoulin hold the record for the most wins in the men's championship with four. The women's record is held by Leontien van Moorsel with six wins.