【Abstract】Objective To verify the clinical effectiveness and safety of using bioimpedance to determine the target body weight of peritoneal dialysis (PD) patients. Methods A total of 75 PD patients were randomly divided into traditional method group and body composition monitor (BCM) group. BCM group used the formula: target body weight = measured body weight - over hydration (OH) + 2 kg, to guide patient volume management. After 6 months, changes of blood pressure, edema degree and brain natriuretic peptide (BNP) were compared between the two groups. Results The OH value by BCM was positively correlated with edema degree (r=0.366, P=0.001), defined daily doses (DDDs) of blood pressure medications (r=0.440, P＜0.001), systolic pressure (r=0.494, P＜0.001), diastolic pressure (r=0.414, P＜0.001), left ventricular end diastolic dimension (r=0.591, P＜0.001) and BNP (r=0.615, P＜0.001), and was negatively correlated with albumin (r=-0.354, P=0.002). In BCM group after 6 months, body weight (60.4±10.6 vs. 59.6±10.2; t=2.988, P=0.005), systolic blood pressure (136.5±23.9 vs. 126.9±20.3; t=2.238, P= 0.033) and the patients with moderate or higher than moderate edema (46.9% vs. 37.5%; χ2=15.469, P＜0.001) decreased; these changes were not observed in control group. Conclusion BCM can be used to help determine target body weight of PD patients.