Objective. The aim of this study was to establish reference values for body composition as measured by Bioelectrical Impedance Analyser (BIA) in adult females without any endocrinological and/or metabolic disorders, according to their body mass index (BMI) grouped as normal, overweight, obese and morbid obese. Patients and Methods. This study was performed in a total of 327 adult females. In addition to the estimation of their body weight, height, waist and hip circumference, their body composition was measured by BIA. The results were statistically evaluated by a computer program usig ANOVA test. Results. Together with the increase of BMI also the percentage of body fat and basal metabolism (BM) increased significantly, while the percentage of body water, fat free mass as well as lean/fat ratio showed a significant decrease. In addition, waist and hip ratio, percentage of body fat and BM showed a significant positive corelation with BMI. Conclusion. These results are recommended to be used as reference values for the studies on body composition, especially to predict the degree of body fatness of obese patients and also nutritional status of patients who need nutritional supports.