Humidity control is necessary for a comfortable and healthy indoor environment. The electro-chemical dehumidification is promising recently due to its economical, space-flexible and en-vironmental-friendly characteristics. In this study, an electrolytic dehumidification system with polymer electrolyte membrane was developed, which size was as small as 10-5~10-6 m3. The dehumidification and energy performance were investigated under various operating conditions. Results showed that this method could dehumidify the air flows. The dehumidifi-cation rate increased significantly with the air temperature, which improved more than 2 times when the temperature increased from 22 to 41°C. It also increased significantly with air flow rates, which the growth trend could be divided into three phases. The current also increased with the air temperature and flow rates. Furthermore, the steady-state energy efficiency ob-tained was 0.43×10-2 g/(J•m2), which was competitive to current electrochemical methods. Therefore, the dehumidification method is promising for independent and portable humidity control.