Kaspars Stupelis (born July 7, 1982) is a Latvian sidecarcross passenger and quadruple World Champion. Stupelis won the 2015 and 2019 World Championship as passenger of Etienne Bax. His previous two world championships were gained when being the passenger in Daniël Willemsen's team. In his time with Willemsen, he also won two Dutch titles in 2003 and 2004, an achievement repeated at the side of Bax in 2012, 2014 and 2015.