The May Bumps 1998 were a set of rowing races held at Cambridge University from Wednesday 10 June 1998 to Saturday 13 June 1998. The event was run as a bumps race and was the 107th set of races in the series of May Bumps that have been held annually in mid-June since 1887. In 1998, a total of 172 crews took part (103 men's crews and 69 women's crews), with around 1550 participants in total.