Abstract: Objective To explore the effect on neurobehavioral functions in welders.Methods WHO neurobehavioral core test battery was applied to exposed and control groups.To choose 51 welders of motorcar factory and 51 workers as cntrol groups who were not exposed to manganese.Results The result showed that scores in tension,depression and anger were significantly lower than those in the control(P<0.01).The digit span,digit symbol,visuaL retention,and manual dexterity of using to the hand,pursuit aiming total number and pursuit aiming right number test were significantly different compared with the control(P<0.01).Conclusion Certain dose manganese had effect on welders who had no self-conscious symptoms at early time,which would result in the disorder of eurobehavioral functions,then induce welders changing of neurobehavioral functions.