OBJECTIVE:The aim of this study was to compare three methods of gonial angle determination on a cephalogram with the method used to find gonial angle in an orthopantomogram, amongst three vertical groups (i.e; hyperdivergent, normodivergent and hypodivergent). Methodology: A total of 178 panoramic and cephalometric radiographs of patients ranging from age 12-39 were used in this study. Gonial angle was constructed by three methods defined by Tweed's, Steiner's and Down's on the cephalogram and was then compared to the method of gonial angle determination on an OPG. Repeated measure ANOVA with Bonferroni correction was used for comparison.