Objectives : To observe physiological changes during clinical acupuncture treatment. Methods : We recruited 40 healthy volunteers who had experienced an acupuncture treatment at least once within the past three years. The experimental group was divided into four groups according to the needling site and frequency of electrical stimulation. Sites consisted of abdomen and legs. Frequencies consisted of 100 Hz and 2 Hz. The procedures of experimental treatment consisted of seven phases, Resting I phase (Resting I), Needle insertion phase (Insertion), Maintenance of needle insertion I phase (Maintain I), Electrical stimulation phase (ES), Maintenance of needle insertion II phase (Maintain II), Needle removal phase (Removal) and Resting II phase (Resting II). We measured the surface electromygraphy (SEMG) through an electrode on the frontalis muscle during all phases consecutively. Results : When SEMGs of all seven phases were analyzed, they significantly increased or decreased according to phases. SEMGs of Insertion, Maintain I, ES and Maintain II phase significantly increased more than RestingI in abdomen and legs groups. SEMGs of the abdomen group were measured as being $4.78{pm}0.74{mu}V$ on Resting I, $16.48{pm}3.97{mu}V$ on Insertion, $46.31{pm}10.56{mu}V$ on Maintain I, $45.88{pm}9.72{mu}V$ on ES, $45.56{pm}9.69{mu}V$ on Maintain II, $18.76{pm}3.05{mu}V$ on Removal, and $3.75{pm}0.65{mu}V$ on Resting II. SEMGs of the legs group were measured as being $3.34{pm}0.35{mu}V$ on Resting I, $12.11{pm}1.76{mu}V$ on Insertion, $36.74{pm}6.99{mu}V$ on Maintain I, $33.57{pm}6.30{mu}V$ on ES, $32.66{pm}6.03{mu}V$ on Maintain II, $14.08{pm}2.15{mu}V$ on Removal, and $2.88{pm}0.32{mu}V$ on Resting II. Conclusions : SEMG changed differently according to processes of acupuncture. Electrical stimulation showed different change of SEMG. Thus, acupuncture treatment may change the status of the autonomic nervous system.