This research was conducted with the aim of determining the relationship between cognitive performance and emotional maturity with sleep quality in teenagers. This research was among descriptive and correlational studies. The statistical population included all teenagers of the second secondary level who were studying in Fardis city of Alborz province. Stratified random sampling method was chosen. Standard questionnaires (Insomnia Severity Index, Montreal Cognitive Assessment Test and Emotional Maturity Questionnaire) were the tools used. Data analysis was done using spss software and to explain the hypotheses from the simultaneous multiple regression test and the test Pearson's correlation was used. The results indicated that cognitive function has a significant relationship with sleep quality, which is inversely related. That is, the sleep quality score is negatively affected by the scores of cognitive function components and the total score of cognitive function. Also, maturity scores Emotional intelligence has a significant relationship with sleep quality, and this relationship is direct and positive, that is, the score of sleep quality is directly affected by the scores of the components of emotional maturity and the total score of emotional maturity. increases clinically. Cognitive performance has a significant relationship with emotional maturity, and this relationship is inverse and in a negative direction.That is, the score of emotional maturity is negatively affected by the scores of the components of cognitive performance and the total score of cognitive performance, and this influence is inverse, that is, with increasing The level of cognitive function, the level of emotional maturity deficiency decreases.