The positive relationship between aerobic capacity and cognitive performance is well known, but there is little information regarding young adults. Therefore, we aimed to test the hypothesis that aerobic capacity (VO2max) correlates with cognitive and academic performance in medical students who have higher academic achievement with academic performance. We included 65 volunteer medical students who were in term 2/6 in this descriptive, cross-sectional study. Body composition and the International Physical Activity Questionnaire and cardiopulmonary exercise test results of all participants were analyzed. Lumosity application with 6 categories of cognitive tests was applied to evaluate cognitive performance. The university entrance exam scores of the students were taken into consideration to assess their academic performance. We observed a significant "positive" relationship between aerobic capacity and some domains of cognitive performance, especially problem solving (p < 0.05), but we did not find a significant relationship between aerobic capacity and academic performance. Consequently, although we confirmed the existence of a positive effect of high aerobic capacity on cognitive performance stated in the literature, we couldn't confirm this for all cognitive domains or academic performance. These results suggest that more comprehensive studies on this subject are needed.