Abstract This study aimed to evaluate the prevalence of Problematic Internet Use (PIU) among adolescents (N = 466) and its possible association with emotional problems and quality of life. Students (Mage = 12.8 years; SD = 1.9) from five public schools in a city in the State of São Paulo participated in this study and completed four instruments: a sociodemographic questionnaire; Internet Addiction Test (IAT); D...