Syfte Syftet med studien var att undersöka samband mellan insatser för att främja fysisk aktivitet i skolan och hälsorelaterad livskvalitet hos elever i årskurs 7. Metod Denna studie genomfördes med en kvantitativ ansats och tvärsnittsdesign. Urvalet bestod av 1139 ungdomar i årskurs 7 (13–14 år) och vuxna representanter från 34 skolor i Stockholmsområdet. Data samlades in genom projektet Hjärnhälsa i skolan under 2019. Elever fick svara på en enkät som inkluderade ett standardiserat formulär om hälsorelaterad livskvalitet (Kidscreen-10 Index). Data om skolans insatser för att främja fysisk aktivitet (undervisningstid i idrott och hälsa, en generell hälsopolicy, organiserade raster, fysisk aktivitet under lektionstid och mobilförbud) samlades in genom en enkät som besvarades av skolrepresentanter samt genom skolans schema. Samband mellan kontinuerliga variabler undersöktes med Pearson korrelationsanalys. Samband mellan kategoriska variabler undersöktes med Spearman korrelationsanalys. Skillnader i kontinuerliga variablerna undersöktes med t-test och variansanalys (ANOVA). Skillnader i de kategoriska variablerna undersöktes med Chi-två-test. Resultat Studien visade att det inte fanns några signifikanta samband mellan någon av insatserna för att främja fysisk aktivitet i skolan och hälsorelaterad livskvalitet. Resultaten visade även att det inte fanns signifikanta skillnader i hälsorelaterad livskvalitet hos elever som gick på en skola som främjar fysisk aktivitet jämfört med skolor som inte hade främjande insatser. Slutsats Denna studie visade att det inte fanns ett samband mellan insatser i skolan för att främja fysisk aktivitet och hälsorelaterad livskvalitet. På grund av ett bristande forskningsläge är det osäkert vilken roll främjande av fysisk aktivitet har för hälsorelaterad livskvalitet, framför allt i svenska skolor. För att dra en slutsats krävs ytterligare forskning inom området. / Aim The purpose of this study was to examine associations between activities to promote school- based physical activity and health-related quality of life among pupils in the seventh grade. MethodThis study had a quantitative methodology and a cross sectional design. The sample was 1139 adolescents in seventh grade (age 13–14) and adult representatives in 34 schools in Stockholm area. Data was collected through the project Hjärnhälsa i skolan (Brain health in school) in 2019. The adolescents answered a survey that included a standardized questionnaire to measure health-related quality of life (Kidscreen-10 Index). Data about school promotion of physical activity (duration of physical education, a general school health policy, organized physical activity during recess, physical activity during lessons and a mobile phone ban) were collected by letting school representatives answer a questionnaire and through school schedules. Associations between the continuous variables were analyzed with Pearson’s correlation. Associations between the categorical variables were analyzed with Spearman’s correlation. Differences between the continuous variables were analyzed with t- test and analysis of variance (ANOVA). Differences between the categorical variables was analyzed with a Chi-square test. Result The results showed that there was no significant association for any of the activities to promote school based physical activity and health-related quality of life. The results also showed that there was no difference in health-related quality of life amongst pupils that attended schools that promoted physical activity compared to schools that did not. Conclusion This study showed that there were no significant associations between activities to promote physical activity in schools and health-related quality of life. Due to scarce research, it is uncertain what role promotion of physical activity has for health-related quality of life for adolescents, especially in Swedish schools. To conclude this, more research is needed.