Nicolas Pieter du Preez (born 1979 or 1980) is a South African athlete in paratriathlon. In 2013, he was the first person with tetraplegia to ever complete an Ironman Triathlon. Du Preez started competing at the Berlin Marathon in 2008 and was a seven-time winner from 2012 to 2018. In international events, du Preez competed at the 2012 Summer Paralympics in the 100m event and won gold at the 2020 Summer Paralympics in the time trial as a H1 competitor. At the UCI Para-cycling Road World Championships, he has won five golds as part of his thirteen accumulated medals from 2014 to 2022. Outside of his athletic career, du Preez works in risk assessment as an analyst.