The author compared patients showing two extremes of incisor vortical relationship to find out differences in craniofacial morphology which might unfluence face height and incisor overbite. The subjects consisted of 53 open-bite cases and the same number of deep-bite cases. The results were as follows : 1. On the averagem the lower face height was significantly greater in open-bite cases than in deep-bite cases. 2. In open-bite cases, gonin-menton length was significantly greater than in deep-bite cases. In deep-bite cases, anterior cranial base length and posteriof cranial base length were significantly greater in open-bite cases. 3. The jaw angle was cignificantly greater in open-bite cases. 4. The gonion-menton-nasion angle was sigificantly greater in deep-bite cases. 5. From geometric standpoint, the increase of jaw and joint angle would increase lower face height, but these two showed negative correlation. 6. The sizes of the jaw and joint angle might be factors of open-bite or deep-bite, but these were not the only variables that determined lower face height. 7. In open-bite cases, there was a closer correlationship between lower face height and the other linear measurments than in deep-bite cases. 8. Considering both linear and angular measurements of facial polygon, all contributed significantly to the lower face height. The nonsignificant variables were jaw and joint angle in open-bite cases, and anterior cranial base lenght, jaw angle, and joint angle in deep-bite cases.