Aim: To determine the prevalence of visual impairment caused by uncorrected refractive errors in students in secondary schools in Birnin Gwari LGA, Kaduna. Nigeria. Materials and methods: A cross-sectional study was carried out with participants recruited by a two-staged random sampling technique with probability proportional to size. A total of 400 students were selected of which 388 were available for screening with Snellen’s chart (a response rate of 97%). All participating students were registered and questionnaire administered. Thereafter, they had distant and near visual acuity tested had distant and near visual acuity tested, unaided and with the pin hole. They also had non cycloplegic objective auto refraction then subjective refraction; test of ocular alignment, anterior and posterior segment examination. Those with distant visual acuity of worse than 6/6 which improved by at least one line of the Snellen’s chart with pin hole or near acuity of worse than N6 were considered ametropic. A spherical equivalent (SE) of -0.50D or less was considered myopia, +1.00D or more as hypermetropia and +/- 0.75DC or more as astigmatism.