[Purpose] We know of no reports on the effects of electro-acupuncture (EA) stimulation, on human skeletal muscle blood flow (MBF), examined quantitatively with a direct method. Therefore, we investigated changes in MBF before, during and after EA with a new clearance method. [Methods] Ten healthy adult volunteers (8 men and 2 women; median age 30.5 years) were given EA to the trapezius at the BL 10 and GB 21 acupoints, employing the left trapezius as the non-EA side to contrast with the right trapezius as the EA side, and using stainless needles of 50 mm length and 0.18 mm gauge. MBF data were surveyed for 2 minutes before EA, for 4 minutes during EA, and for 4 minutes after EA, and a total of10minutes were analyzed l(?). Blood pressure and heart rate were simultaneously measured. [Results] MBF on the EA side increased significantly during EA (p < 0.05). On the other hand, diastolic blood pressure and heart rate were shown to decrease during EA (p < 0.05). [Discussion] These results, showing that MBF increased on the EA side, while diastolic blood pressure and heart rate decreased, suggest a regional muscle pump action with EA. [Conclusion] In evaluating a new, direct means of quantitatively examining _99mTc0_4- clearance, an increase in MBF with right side EA stimulation was clearly shown. Because the present method is simpler and easier, and higher in accuracy than past methods, we believe it may be used more aggressively in future clinical studies of acupuncture/moxibustion.