The purpose of this study is to provide the reference data for estimating body composition and developing equations for prediction of percent body fat. This study was designed of two aspects: Comparison of percent body fat measurements between two operators. comparison of percent body fat measurements among four instruments. Percent body fat of college girls(n=71) aged 18-24 was measured by skinfold thickness, near-infratred interactance(Futrex-5000), and bioelectrical impedance analysis (TBF-105, Spectrum II). All measurements were duplicated & measured by two operators. The results are summarized as follows: Percent body fat observed from two operators had no significant difference. There was significant difference from four instruments. However, we found close relation between Skinfold thickness & TBF-105, Spectrum II & Near-infrared interactance. Four instruments have several assumptions and limitations. Therefore, many researches for developing new equations are required for Korean people.