Objective To study the efficacy of transcutaneous electrical acupoint stimulation (TEAS) on rehabilitation training for children with autism and primary mechanisms.Methods One hundred and twenty four autistic children receiving rehabilitation training were divided into a control group (n=39) and a TEAS treatment group (n=37).The control group received rehabilitation training, the treatment group received TEAS for 60 sessions after rehabilitation training.Childhood Autism Rating Scale (CARS), Autism Behavior Checklist (ABC), Aberrant Behavior Checklist (AbBC), Adaptive Deviation Quotient (ADQ), Sleep status questionnaire and Food choice questionnaire were used for outcome assessment.Results (1) The total scores of CARS (P<0.05) andABC (P<0.05) decreased significantly after TEAS intervention, specifically in Emotion (P<0.05), Anxiety (P<0.01) and Intelligence (P<0.05) factors in CARS, Sense (P<0.01) and Social communication (P<0.01) factors in ABC.(2) The kinds of rejected food reduced after TEAS treatment (P<0.05), especially in vegetables (P<0.05), fruits (P<0.01) and snacks (P<0.05).(3) TEAS was more effective on children with passive (P<0.05) but not active-but odd social interaction style.(4) The plasma arginine-vasopressin (AVP) increased after TEAS treatment (P<0.01).(5) The plasma oxytocin (OT) decreased in both groups after 3 months intervention, and less decrease were found in TEAS group (P<0.05).(6) The change of plasma AVP was positive correlation with Interpersonal communication (P<0.05), Auditory (P<0.05) and Sense (P<0.01) factors in CARS.Conclusion TEAS combined with habilitation training has a better therapeutic effect than that of simple rehabilitation training for autistic children with passive social interaction style, and which was related with plasma AVP and OT.