This study was carried out to determine the effects of instruction done by traditional instruction methods and computer- supported PowerPoint presentation in teaching on students' achievement. The study was carried out in Education Faculty of Inonu University during the spring term of 2002-2003 academic year. In the study, pretest/ post- test experimental design with nonequivalent control group was used. The Department of Social Studies Teacher Training selected randomly was defined as the experimental group and the Department of Pre-School Teacher Training was defined as the control group. PowerPoint lecture material consisted of 17 slides. Independent groups t- test was used in the statistical analyses. Between the experimental and the control group, p students' post- test and achievement scores, significant differences were found in favor of the experimental group in which PowerPoint presentation supported instruction was used.