The objective of this paper is to establish the factors that influence students' acceptance and use of online registration system in a South African university. This study used the Unified Theory of Acceptance and Use of Technology (UTAUT). The study is informed by empirical evidence of a case study of Tshwane University of Technology (TUT), with survey sample of 300 students from four campuses: Pretoria, Shoshanguve, Ga-rankuwa and Polokwane. The analysis of the results shows that much as there is no significant correlation between performance expectancy and behavior intention, the constructs' reliability shows that UTAUT is a good model for predicting acceptance and use of online registration system. However this study recommends that the constructs of UTAUT need to be modified in order to have a better prediction model. The study contributes to the literature of students' acceptance, adoption and use of web-based tools in the academic arena.