The study investigated the prevalence of peer victimisation among secondary school students in a state in South Western Nigeria. Participants consisted of 385 secondary school students selected from ten secondary schools across 10 local government areas in Osun State, Nigeria. The participants, aged between 10 and 19 years, were stratified into junior and senior secondary classes. The Multidimensional Peer-Victimisation Scale was used to collect data on four types of peer-victimisation commonly found among students. Results from descriptive and inferential analysis of data indicate that the majority of participants reported overall high levels of peer victimisation with attack on property as the most frequent form of peer victimisation. There were significant differences between male and female participants on all forms of victimisation with females reporting higher level of social victimisation, verbal victimisation and attack on property than males. The study also found that while students' level of study did not significantly influence the extent to which they were victimised by peers, age was a significant factor in reported levels of peer victimisation. The study brings into focus the need to make guidance services functional in Nigerian secondary schools to overcome the problem of bullying and peer victimisation. (Contains 6 tables.)