Literature reports suggest that subjective sleep quality is associated with nutrient intake in elderly people and workers. However, few studies have suggested an association between objective sleep quality and dietary intake in adolescents and young women. We hypothesized that objective sleep quality is associated with dietary intake in adolescents and young women. We evaluated the association between energy and nutrient intake and objective sleep quality in adolescents and young Japanese women. In a cross-sectional study of 80 women aged 18-27 years, dietary intake was assessed using the self-administered diet history questionnaire. Objective sleep quality was assessed by actigraphy. Lifestyle characteristics, dietary habits, and mental health were assessed using specific questionnaires. Subjects were classified into 3 groups according to sleep efficiency (SE <80%, 80%-85%, and ≥85%), and the relationships between dietary intake and objective sleep quality were statistically evaluated. No significant differences occurred in lifestyle characteristics, physical activity levels, eating behavior, and mental health status among the 3 SE groups. Energy intake was significantly lower in the low-SE group than in the middle- (P = .004) and high- (P = .015) SE groups. Protein intake was significantly lower in the low-SE group than in the high-SE group (P = .034). The mean energy-adjusted intakes of vitamin K, vitamin B2, potassium, magnesium, iron, zinc, copper, and tryptophan were significantly lower in the low-SE group than in the high-SE group. Adequate energy intake and a high-quality diet including vitamins, minerals, and tryptophan may result in high sleep quality and help prevent sleep problems.