Introduction: Theory and research support the idea that subjective well-being (positive / negative affect and life satisfaction) is a substantial construct in understanding psychological well-being and mental health. The relevance of life satisfaction in variables affecting psychological well-being has been studied. Life satisfaction in adolescents and its association with sex, age, parental educational styles, peer attachment and emotional intelligence was researched. Groups were compared according to degree of life satisfaction and its relationship with these variables. Method: The sample was composed of 285 secondary school students (49.8% male), average age 15.09 years (12 to 19), and self-report measures of variables were applied to be analyzed: "Satisfaction with Life Scale-Child" (SWLS-C), "Parental Educational Style of Adolescents," "Inventory of Parent and Peer Attachment" (IPPA) and "Trait Meta-Mood-Scale-48" (TMMS-48). Results: Results showed a significant high level of satisfaction among adolescents. A significant higher score among boys compared to girls was confirmed, as in the younger compared to older. Correlations were statistically significant between life satisfaction and all dimensions from Parental Educational Style analyzed, except Behavioral Control; with Alienation and Confidence of Peer Attachment; and with Emotional Intelligence Clarity and Repair, as well as statistically significant differences among satisfaction groups in 12 of the 19 variables analyzed. Discussion and Conclusion: Promoting life satisfaction in adolescents is increasingly relevant, due to the role it may play in achieving good psychological adjustment, thus contributing to the promotion and prevention of mental health.