The purpose of this study was to predict the prognosis of class III malocclusion treatments. 25 patients selected for this study were devided into two groups by the stability of dentitional, skeletal and soft tissue profile improvement. One was stable group which consisted of 12 children and the other was relapse group with 13 children. Various measurements in initial lateral cephalogram were calculated and analyzed by t-test, correlation coefficient and discriminant analysis. The results of this study were summarized as follows 1. In both stable and relapse groups, there was not distinct difference in the antem-posterior. skeletal relationship(P<0.05). 2. As the result of wits, AB to occlusal plane angle and occlusal plane to mandubular plane angle, the occlusal plane of relapse group was stopper than that of the stable group. 3. In correlation coefficient analysis, the overjet and the occlusal plane to mandibular plane angle showed significant correlations (P<0.001, P<0.01). 4. The discrminant function was obtained from three major influential measurements; overjet, AB to occlusal plane angle and articular angle,s and´ this function could discriminate correctly in .:% of these -samples.