Controversy has been existed on the effect of occlusal factor on bruxism. The purpose of this study is to evaluate the effect of occlusal factor on bruxism by clinical examination and photo-occlusion analysis. The patient group and control group are selected for this study. The results show that (1) the occlusal status in centric occlusion and eccentric articulation of the patient and control group has no significant difference; (2) the occlusal contact strength and distribution in centric occlusion of the patient and control group has no significant difference; (3) occlusal interferences are existed in different extent both in patient group and control group. This expresses that most of the subjects can compensate this kind of occlusal disorder without feeling any discomfort; (4) This can be concluded that occlusal factor is not an major causal factor on bruxism.