The purpose of this study is to compare the academic performance and the physical self-concept on a group of high school students according to their physical activity level. 124 students, average age 18,1 (+/- 0,60) were evaluated. The level of physical activity was determined with the IPAQ questionnaire. The physical self-concept was evaluated using the Physical self-Description Questionnaire (PSDQ). The average grades in Linguistics and Mathematics were used to determine the Grade Point Average (NEM, for its acronym in Spanish). Results showed that male students have a more positive PSC (p<0,000) and NEM (p<0,033) than female students. It also showed that male and female students that are more active have better PSC and NEM than the ones with low physical activity (p<0,05). From these results it is possible to conclude that teenagers, both male and female, that have physical activity on a regular basis get better grades and show a more positive physical self-concept than the ones who are not as active.