Background: Adolescent period is the critical period of growth and development. Undernutrition during adolescence can impair growth and development and result in long term health consequence. Aims: To study the nutritional status of early adolescents its association with sexual dimorphism. Methods: This cross-sectional community based study has conducted among 355 adolescent (189 boys; 166 girls) aged 11-14 years of the rural areas of Paschim Medinipur district, West Bengal, India. Anthropometric measurements including height, weight, midupper arm circumference were taken following standard technique. Body mass index (BMI) was calculated to determine the nutritional status using international BMI cut-off point for children and adolescence from 2 to 18 years of age. Statistical package SPSS  is employed for one way ANOVA and Student- ‘t’ test of the data. Results: The mean BMI for girls (16.71±3.02 kg/m2) were higher than boys (15.97±2.26 kg/m2) with t=2.631 (P=0.009). There is a significant age difference (P<0.001) existed for weight, height and MUAC. The prevalence of thinness and overweight was 51.83% and 4.51% respectively. The prevalence of thinness was grater among the boys (52.91%) than the girls (50.60%). Conclusion: The present study indicates high prevalence of thinness among adolescent in the area of study. A comprehensive strategy should be implemented in disadvantaged groups to prevent adolescent undernourishment.