Background: Malnutrition in adolescent girls causes alterations in growth, development, reproductive cycles, health and wellbeing. Objectives: To evaluate the dietary pattern, nutrient intake and nutritional status among adolescent school girls. Methods: Study was conducted among 386 girls (11-15years), purposively selected from government schools of Puducherry. Dietary intake was obtained using 24-hour food recalls, average nutrient intake per day was calculated using Nutrition Society of India diet calculator and compared with Recommended Dietary Allowances 2020. Food groups intake was compared with portions recommended by National Institute of Nutrition. The Food and Agriculture Organization’s Minimum Dietary Diversity for Women was modified to determine the Dietary Diversity. Data was analyzed using SPSS 21.0. Results: The Body Mass Index of girls (12.88±1.11 years) revealed the prevalence of both under (28.8%) and over-nutrition (48.7%). Iron Deficiency Anaemia among (30%) of the underweight girls was ascertained by serum ferritin ≤15ng/ml. The average intake of food groups was less than guidelines and the Dietary Diversity Score was 5.93 ±1.18, showing minimum adequacy. The percentage of adolescents with low Dietary Diversity scores was 40.2%. Low socioeconomic status and parents’ education were significant determinants. The average intake of energy, calcium, vitamin A, iron, zinc, folic acid was significantly lower, fat protein and vitamin C being higher than the recommendation. Conclusion: Improving food quality, diversity in consistent meal schedule and portion size in accordance with guidelines needs to be emphasized to prevent triple malnutrition.