Background: Anemia is a major nutritional problem worldwide. In 2018, at least 1.62 billion people were affected by anemia, and 33% were school children. Anemia in female adolescents contributes to high rates of maternal and infant mortality. This study aims to analyze the determinants of anemia among female adolescent at the individual level and at the school level. Subjects and Method: This study used a cross sectional research design. The study was conducted in Klaten Regency in February 2020. Sampling used was probability sampling with a total of 200 female adolescents aged 15 to 19 years old. The independent variables include knowledge, family economy, menstrual pattern, consumption of blood supplement tablets, and nutritional status. The dependent variable is anemia. Data were collected by using the Easy Touch brand hemoglobinometer, weighing scale, microtoice and questionnaire. Data were analyzed using multilevel multiple logistic regression with a stata of 13. Results: The results of this study indicated that good knowledge (b=-2.29; 95% CI= -4.23 to -0.32; p= 0.022), family economy ≥Rp 1,947,821 (b= -2.73; 95% CI= -4.58 to -0.75; p= 0.006), regular menstrual patterns (b= -2.29; 95% CI= -4.58 to -0.75; p= 0.001), blood supplement consumption (b= -3.22; 95% CI= - 8.96 to -2.17; p= 0.001), normal nutritional status (b= -3.36; 95% CI= -6.65 to -1.74; p= 0.001) reduce the incidence of anemia in adolescents. Variations at the school level indicate a contextual influence on the incidence of anemia in adolescents (ICC= 59.36%). Conclusion: There was a statistically significant influence of knowledge, family economy, menstrual patterns, blood supplement consumption and nutritional status on the incidence of anemia in adolescents. Variations at the level of school indicated that there was a contextual influence on the incidence of anemia in adolescents. Keywords: Multilevel, Anemia, Adolescents, School Correspondence: Nurmala Dewayanti. Masters Program in Public Health, Universitas Sebelas Maret. Jl. Ir. Sutami 36A, Surakarta 57126, Central Java. Email: nurmaladewayanti@gmail.com. Mobile: +6287734875004.