Irvette van Zyl (born Irvette van Blerk; 5 July 1987) is a South African long-distance runner and women's 50km ultramarathon world record holder. She competed in the marathon at the 2012 Summer Olympics but did not finish the race. She has twice participated in the London Marathon and set her previous best time of 2:31:26 hours there in 2013. In 2021 she improved this time by almost 3 minutes to 2:28:40 at the Xiamen Marathon in Siena, Italy.