Rohan Dennis (born 28 May 1990) is an Australian former cyclist, who competed professionally in the track and road disciplines of the sport for five different teams.
Having been a member of the Australian team pursuit squad that won consecutive world titles at the UCI Track Cycling World Championships in 2010 and 2011, Dennis transitioned to road racing in 2013. Dennis took more than thirty wins in his career, the majority coming in individual time trials – including consecutive wins at the UCI Road World Championships in 2018 and 2019, four Australian National Time Trial Championships victories, and stage wins at all three Grand Tours. He also won the 2015 Tour Down Under and is a former holder of the Union Cycliste Internationale's hour record, having completed a distance of 52.491 kilometres (32.616 miles) in 2015.
On 31 December 2023, he was arrested and charged with causing death by dangerous driving, driving without due care, and endangering life, after the vehicle that he was allegedly driving killed his wife Melissa Hoskins in Adelaide.