Acupuncture increases brain levels of arginine-vasopressin (AVP) and oxytocin (OXT), which are known to be involved in the modulation of mammalian social behavior. Transcutaneous electrical acupoint stimulation (TEAS) is often used clinically to produce a similar stimulation to that of acupuncture on the acupoints. In the present study, TEAS was applied to children with autism to assess its therapeutic efficacy. Seventy-six autistic children receiving rehabilitation training were divided into 2 groups: a treatment group receiving TEAS 30 min per day, 5 days per week for 12 weeks (n = 37) and a control group without TEAS treatment (n = 39). A series of rating scales was used in outcome assessment. Plasma levels of AVP and OXT were determined by enzyme immunoassay (EIA) before and after treatment. The TEAS group showed a significant improvement over the control in their emotional response, fear or anxiety, level/consistency of intellective relations and general impressions on the Childhood Autism Rating Scale (CARS) as well as improvements in the sensory and related factors in the Autism Behavior Checklist (ABC). In addition, the varieties of accepted food increased after TEAS treatment. It appears that TEAS was effective in autistic children who showed passive and aloof behavior, but not in those who were active but odd. The plasma level of AVP was significantly higher in the TEAS group than in the control group after the intervention. In addition, the change in the plasma AVP level paralleled the improvement of some of the behavior factors in CARS, including adaptation to environmental change, listening response, perceptive response and fear or anxiety. It is concluded that TEAS is effective for the treatment of autistic children with a passive and aloof social interaction style. Changes in plasma levels of AVP and possibly OXT may be involved in mediating the therapeutic effect of TEAS. (C) 2012 Elsevier Ltd. All rights reserved.