The present study aimed to evaluate the association of frequency of consuming takeaway meals and meals out with diet quality of UK adolescents. The Diet Quality Index for Adolescents (DQI-A) tool was used to assess diet quality, where adolescents' food intake was based on 4d diary records obtained from the UK cross-sectional National Diet and Nutrition Survey (NDNS) rolling programme Years 1-6. Models included confounders. The DQI-A relies on three components, specifically diet quality, diversity and equilibrium, which reflect the degree of adherence of an adolescent's diet with food-based dietary guidelines.ParticipantsBritish (n 2045) adolescents aged 11-18 years. Mean diet quality score for all adolescents was 20·4 % (overall DQI-A score range: -33 to 100 %). After adjusting for age, gender and equivalised household income, DQI-A% score was higher for low and moderate takeaway consumers by 7·4 % (95 % CI 5·5, 9·2; P<0·01) and 3·5 % (95 % CI 1·9, 5·1; P<0·01), respectively, v. frequent consumers. Significant differences were also observed between low, moderate and frequent takeaway consumers among all DQI-A components and sub-components (P<0·05), except for the diet adequacy sub-component (DAx). Results for frequent consumption of meals out were similar but attenuated and not statistically significant for individual components before or after adjusting for confounders. Frequent consumption of takeaway meals may have a negative impact on adolescents' diet quality and therefore policies to reduce the intake of takeaways should be considered in this age group.