Introduction. Sleepiness in students has an impact on their learning, focus and memory. Sleepiness is caused by multiple factors. Therefore, our objective was to estimate the frequency of sleepiness in Peruvian students and assess its relation to lifestyle and sleep habits. Methods. Cross-sectional study conducted on first through fifth year secondary students. The Spanish version of the pediatric daytime sleepiness scale (0 to 32 points) was administered and sleep and demographic characteristics and harmful habits, among others were investigated. Excessive sleepiness was considered as a score higher than 20 points, and its association was assessed using raw and adjusted odds ratios. Results. The study included 586 students; the average score in the pediatric daytime sleepiness scale was 13.0 ± 5.5; 11.9% of students had excessive sleepiness. Smoking was associated with excessive sleepiness, with an adjusted OR of 6.9 (95% CI: 2.9-17.0); alcohol consumption showed an OR of 4 (95% CI: 1.5-10.5), and practicing sports showed an OR of 0.5 (95% CI: 0.3-0.9). Likewise, having a bad sleep quality (OR: 5.4; 95% CI: 3.1-9.5) and taking more than 60 minutes to fall asleep (OR: 2.5; 95% CI: 1.1- 6.0) were associated with a higher probability of having sleepiness. Conclusion. Sleepiness was observed in 12% of the studied population, and was found to be lower than the rates described in studies with different populations. Excessive sleepiness is associated with smoking and frequent alcohol consumption, a lower level of sports practice, and bad sleep habits.