Impedance measurement is widely used at present, it can be applied to clinical monitor such as blood leakage monitoring during hemodialysis. However, some patients have the symptom called 'cold sweating' that may occur during hemodialysis treatment. It affects the results of impendence measurement. So to distinguish the difference between blood leakage and sweat at the same time, it could provide better method for blood leakage monitoring during hemodialysis. This study presented a wearable device with a conductivity sensor for sweat and blood leakage monitoring based on wide frequency range analysis. The device had self-calibration function to reduce the interference in environment. The experimental results show that the proposed wearable device could distinguish blood concentration that mixed artificial sweat successfully. Overall, it has high potential application in clinical use.