Dennis Olsen (born 14 April 1996) is a Norwegian racing driver. Born in Våler, Norway, Olsen began Karting in his native Norway aged six. After winning numerous junior titles, he stepped up to the KF3 class in 2009, winning the Norwegian title. He retained his title in 2010, a year which also saw him finish second in the Junior Monaco Kart Cup and third in the German Junior Karting Championship. In 2011, Olsen won his third consecutive Norwegian KF3 title, the German KF3 championship and the WSK Cup Final KF2 titles. For his final year of karting in 2012, he successfully defended his WSK Cup Final KF2 title and also won the prestigious German KF1 karting championship.
Olsen began his single-seater career in early 2013, racing in the New Zealand-based Toyota Racing Series, becoming the first Norwegian driver to enter the series.