Objectives : Assuming that the characteristic of meridian system has been similar to this of electric potentials in human body and that measurements of electric potential at well(井穴) and sea(合穴) points in branches of the twelve meridians(WSBTM) will be representative of measurements of the twelve meridians, to measure the electric potentials of 13 patients with Arthroncus of Knee(슬안풍<膝眼風>, AK), to find out the characteristic of meridian system in patients with AK. Methods : Electric potentials of well and sea points in the meridians in twenty one patients with the pain in the lion diagnosed as AK were repeatedly measured by physiograph(PowerLab). Measurements of those electric potentials were analyzed by factor analysis. Results : Their electric potentials at the left and right side were factors which are different from each side. In the left side, Factor 1 included Small Intestine, Pericardium, Spleen, Kidney meridian, and Factor 2 included Heart, Tripple Energizer, Bladder, Liver meridian. Factor 3 included Large Intestine, Stomach, Gall bladder meridian, and Factor 4 included Lung meridian. In the right side, Factor 1 included Heart, Pericardium, Tripple Energizer, Spleen, Bladder meridian and Factor 2 included Lung, Liver, Gall bladder meridian. Factor 3 included Small Intestine, Stomach, Kidney meridian and Factor 4 included Large Intestine Meridian. Conclusions : The electric potentials of AK differ from those of normal bodies as well as of bodies with other diseases-shoulder lesions, waist lesions, Lumbago due to Strain and Contusion-. Thus electric potentials of well and sea points might be the representative meridian to show their characteristics.