Despite increasing concerns about stress levels in adolescents, knowledge is scarce about what boys and girls from different social backgrounds find stressful. This cross-sectional study explored gender and class patterning of perceived stress and reported stressors in a sample of 1,663 17-year-old Swedish students. The students, especially girls, were highly stressed. No class difference (indicated by educational programme) was found. Performance-related stressors (e.g. school work) and stress due to pressure on looks was mainly patterned by gender (girls), whilst relational stressors were patterned by class (vocational programme students). There was a complex gender and class patterning of stress due to school work and lack of money. The interplay of gender and class inequalities should be acknowledged in identifying determinants of stress in young people. Challenging normative ideals and implementing policies aiming at reducing gender and class inequalities are central components for stress-reducing interventions in, for example, schools.