The purpose of this study is to evaluate the lower leg swelling using EMG measured with our new voltage divider technology, by which the internal impedance of lower leg can be estimated. The amplitude of EMG measured without voltage divider was compared to it with voltage divider. Eleven healthy subjects (24.3±5.1 y.o.) participated in this study. Six female (swelling group) were asked to work at desk for six hours, and five male (control group) were asked to work a regular day. The internal impedance was calculated and calf circumference was measured before and after desk work. Results show that internal impedance in swelling group significantly decreased with increase in calf circumference, and our new evaluation method was proved to be effective for the evaluation of lower leg swelling.