【Abstract】 Objective To evaluate volume status in hemodialysis (HD) patients by modified bioimpedance spectroscopy - calf bioimpedance ratio (CBIR). Methods Calf bioimpedance was measured by bioimpedance spectroscopy. As an index of volume status, CBIR was calculated as follows: CBIR = impedance of 200 kHz / impedance of 5kHz. Reference CBIR range was obtained from 157 healthy volunteers. The volume status of 117 HD patients post-dialysis was assessed using the CBIR from healthy volunteers as the reference CBIR range. Results CBIR of the healthy volunteers was 0.774±0.028, the reference range was thus defined as 0.746～0.802 (mean±SD). CBIR was significantly higher in patients post-hemodialysis than in healthy volunteers（0.790±0.033 vs 0.774±0.028, P＜0.001). HD patients were divided into three groups according to the CBIR: high CBIR group (＞0.802), normal CBIR group (0.746 ~ 0.802), and low CBIR group (＜0.746). There were 43 patients in high CBIR group (36.8%), 62 patients in normal CBIR group (53.0%), and 12 patients in low CBIR group (10.2%). The doses of antihypertensive agents were not significantly different among the three groups. Nevertheless, hypertension was significantly higher in high CBIR group than in normal CBIR group (p=0.008) and low CBIR group (p=0.003). Conclusions Calf bioimpedance measurement may be an effective method for the evaluation of volume status in hemodialysis patients.