Objective: To provide data for exploring the material basis of Acupoints and the relation of accumulation of calcium and vessels at Acupoints .Methods: (1) The distribution characteristics of vessels on tibial side of the interosseous membrane (ST channel 3rd, 4th, 5th, 7th cun ) were observed on Chinese ink vascular perfusion adults legs. (2) The content of calcium on ST channel were determined by proton induced X ray emission analysis. Results: (1) The average density (Aa%) of vessels at the 3rd, 4th, 5th, 7th cun areas of ST channel was significantly higher than that between them ( P