Malpositioned anteriors teeth can aethetically influence, self-appearance, the function of mastication and speech. Malpositioned teeth refers to altered positioning of one or more teeth from a well-alligned jaw. In general, boy’s jaw is bigger than girl’s. This enable to makes difference risk of malpositioned anteriors teeth between boy and girl. The aim of this study to find information about to detect risk difference malpositioned anteriors teeth in student of SMPN 6 Yogyakarta based on sex. Research used observational with cross sectional. The subjects of study were entire student of class VII SMPN 6 Yogyakarta that fulfil criteria and got that is 211 students are 91 students of boy and 120 of girl students. The objects of this study are jaw of anteriors teeth on and lower jaw. The evaluation malpositioned anteriors teeth was conducted by using form investigation based on sex are boy and girl, evaluation appropriate criteria prevalence malpositioned anteriors teeth which cover mesioversion, distoversion, buccoversion, palatoversion, linguoversion, labioversion, torsiversion, transversion and axiversion was scored 1, while normal position was scored 0. The results of the research were obtained by applying statistics method which used cross tabulation to obtain Odds Ratio (OR) and appropriate magnitude OR = 0.59, OR < 1 (Protective risk factor), that meaning boy sex will be protected to the happening malpositioned anteriors is compared boy sex. From the research, it can be concluded that risk malpositioned anteriors teeth in girl student SMPN 6 Yogyakarta which was high than boy students.