This research work is a study on the Impact of Internet Usage on Academic Performance of undergraduate students using Ambrose Alli University Physics undergraduate, Edo State as a case study. The research design adopted was sample techniques using questionnaires as the instrument for data collection. The population of the study was the students of the Ambrose Alli University of Edo State, with students randomly selected making a total sample of 154 students whom were issued questionnaires. Out of the 154 questionnaires distributed, 154 were dully respond. Data collected were analysed using sample techniques and graphical representation. The findings revealed that Internet is one of the beneficial tools in this era of IT not only for business but for academic point of view and enhances the skill and capability of students which assist them in studies and professional life. It also revealed that some of the problem encountered in the usage of the Internet includes lack of computer skills, slow internet server and problem of paying for online services. The study recommends that the university should embark on Information literacy/sensitization programme for student’s in order to effectively harness the various web based electronic resources it is subscribed to.