University of Pretoria Renée Hložek (born 15 November 1983) is a South African cosmologist, Professor of Astronomy & Astrophysics at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto, and an Azrieli Global Scholar within the Canadian Institute for Advanced Research.

She was named a Sloan Research Fellow in 2020, and received the Rutherford Memorial Medal from the Royal Society of Canada.

[13] In 2013 she took part in the Science Train started by Lucianne Walkowicz at Princeton, where she took to the New York City Subway to talk to the public about astronomy.

[15] She continues to work with the polarisation instrument on the Atacama Cosmology Telescope, alongside data from Planck and Wilkinson Microwave Anisotropy Probe and BICEP and Keck Array.

[19] In 2020 she was named a CIFAR Azrieli Global Scholar in 2019,[20] awarded a Sloan Research Fellowship,[21] and the Rutherford Memorial Medal in 2024.