Background: The substance-based on research data from Health Basic (Riskesdas) 2018, the prevalence of anemia in teenage women in Indonesia by 32%. This means 3-4 out of 10 teenagers Princess suffering from anemia. The factor that exacerbates anemia in teenage princesses is the lack of intake of the substance iron, where the substance iron in teenage princesses is really needed by the body for accelerated growth and development. Besides that, teenage princesses experience menstruation every month, so they need it. Meanwhile, the amount of food consumed is not fulfilled, because the factor wants to slim. The aims study was to determine the relationship between body mass index (BMI) and the behavior of consuming iron supplement tablets with the incidence of anemia in adolescent girls at the Private Vocational High School Keluarga Bunda Jambi.
 Method: The method is an analytic study with a cross-sectional approach. The research sample was all students in grades X and XI at the Private Vocational High School Keluarga Bunda Jambi, totaling 52 people, (total sampling). Data collection was carried out in May 2021 using a questionnaire and the hemoglobin value was obtained through examination of the hematology analyzer at the Medical Laboratory Technology of Health Polytechnic of Jambi, data analysis using Chi-square.
 Result: The results of the study showed that the incidence of anemia in young women was 25%. Based on BMI, the most common anemia occurred in the normal BMI group (46.1%), followed by a thin BMI of 30.7%. The highest incidence of anemia (92.3%) was in the group of adolescent girls who did not take iron tablets regularly
 Conclusion: There is a relationship between adherence to taking Iron Blood tablets and the incidence of anemia with a P-value of 0.000, but there is no significant relationship to BMI.