In this study the prevalence of internet addiction was ascertained among students of a university in Nigeria, using a survey design method. A sample of 1448 students was selected through a proportionate sampling technique. Data were collected using Young's (1998) Internet Addiction Test. Fourteen percent of the students exhibited severe levels of internet addiction, with a higher rate among male than female students. Internet addiction was observed to be more prevalent among students who were residing on campus. The findings of the study are important for counselling psychologists, psychiatrists and policymakers.