The May Bumps are a set of rowing races, held annually on the River Cam in Cambridge, England. They began in 1887 after separating from the Lent Bumps, the equivalent bumping races held at the end of February or start of March. Prior to the separation there had been a single set of annual bumps dating from its inception in 1827. The races are open to all college boat clubs from the University of Cambridge, the University Medical and Veterinary Schools and the Anglia Ruskin Boat Club. The May Bumps takes place over four days in mid-June and is run as a bumps race.

The River Cam is the main river flowing through Cambridge in eastern England. After leaving Cambridge, it flows north and east before joining the River Great Ouse to the south of Ely, at Pope's Corner. The total distance from Cambridge to the sea is about 40 mi (64 km) and is navigable for punts, small boats, and rowing craft. The Great Ouse also connects to England's canal system via the Middle Level Navigations and the River Nene. In total, the Cam runs for around 69 kilometres (43 mi) from its furthest source to its confluence with the Great Ouse.