The study examined the influence of online social networking usage on academic performance among secondary school students. The study was guided by three research questions and 3 null-hypotheses that were tested at 0.05 level of significance. Descriptive research design using survey method was adopted. The population of the study consist of 5020 students which were drawn from six senior secondary students in Zaria, Giwa and Sabon Gari Local Governments in Zaria metropolis. A simple random sampling technique was used to select 10% of the population of the students consisting 502 respondents. The instruments tagged influence of online social networking usage on academic performance among secondary students (IOSNUAP) developed by the researcher and Mathematics and English tests developed by experts were used for academic performance. Descriptive statistics of frequency counts, simple percentage were used to present the demographic data of the respondent, mean score and standard deviation were used to analyse the research questions. Independent t-test was used in testing null-hypotheses one and two while analysis of variance (ANOVA) was used for hypothesis three. All hypotheses were tested at 0.05 alpha level of significance. The result indicates significant influence of online social networking usage on academic performance of male than female in Zaria metropolis. This suggests that the academic performance of the male is lower than that of the female because of the influence of online social networking usage has on their academic performance. Age bracket 12 - 14 in Zaria metropolis had negative significant influence of online social networking usage on their academic performance. This suggests that online social networking usage has negative influence on age bracket 12 - 14 years than 14-16. Very frequent users had higher negative influence of online social networking usage on academic performance in Zaria metropolis than their counter parts. This suggests that all the users had influence of online social networking usage but the negative influence is more on the very frequent users. The researcher recommended among others that counsellors should adequately mentor students on the influence of online social networking usage