The aim of this study was to analyze the prevalence and association between sleep quality with gender and age and to examine the relation between age and the components of the PSQI in institutionalized adolescents. High school internal students of both genders, aged between 14 and 19years old, were analyzed. After a full clinical evaluation, the Pittsburg Sleep Quality Index Score was obtained from all participants. We studied 210 participants [male: 15. 7±1.2years; BMI: 21.7±2.6kg/m2; female: 15.7±1. 2years; BMI: 21.9±4.5kg/m2]. Poor sleep quality was present in 137 (65.3%) participants and was predominant among girls than boys (PSQI=76.3 vs 55.8%; p<0.001), respectively. There were positive correlations between PSQI components with age in boys (sleep latency: R=0.23; p=0.02; sleep duration: R=0.28; p<0.01 and overall sleep quality: R=0.21; p=0.03), but not among girls. Institutionalized girls have worse sleep quality than boys and positive correlations between sleep quality components with age were only present among boys.