Considering inconsistent previous findings on the relationship between academic achievement and sports engagement, the study was conducted with the aim to examine the relations between students' academic achievement and selected indicators of sports engagement, including the type of sport (individual/team), years of sport experience and the level of competition. The sample consisted of 194 secondary school third-graders, 89 males and 105 females. As for the academic achievement, 85 participants achieved an excellent overall score in the previous school year, 44 achieved a very good overall score, and 65 achieved a good overall score. In addition, 87 participants were non-athletes and 107 were athletes, with 34 of them being engaged in individual sports and 73 in team sports. Descriptive statistics was applied, as well as contingency tables (Chi-square test) and Freeman-Halton extension of the Fisher exact probability test. The results indicate that the academic achievement of athletes and non-athletes does not differ significantly. The relations between sports engagement and academic achievement were more prominent in male students; non-athletes had significantly better academic achievement than athletes (X-2 (2, N = 89) = 10.536, p = .00). As for the whole sample, students engaged in individual sports achieved better academic results than those engaged in team sports (X-2 (2, N = 107) = 6.44, p = .04). In the female student subsample the relationship between academic achievement and sports engagement was more related to sport experience; students who have been training for a longer period turned out to be better in terms of academic achievement. The level of competition was not identified as a significant variable in explaining the differences in academic achievement.