Abstract: Objective：To explore the difference of somatosensory and jaw function between patients with unilateral temporomandibular joint (TMJ) pain and normal subjects by quantitative sensory test and opening ranges. Methods：20 patients suffering from unilateral TMJ pain and 20 healthy controls were enrolled in this study. Visual analogue scale (VAS)，opening ranges (OR) and mechanical pain threshold (MPT), pressure pain threshold (PPT) on both TMJ were measured and compared. Results：VAS of patients were higher than that of controls (P<0.001), but opening ranges were all smaller than controls (P<0.001). Both MPTs and PPTs of pain side of the patients were lower than ipilateral side of controls (P<0.05). MPTs and PPTs were also lower in pain side than those in contralateral side of TMJ in patients (P<0.05). Conclusions：TMJ pain patients demonstrated high sensitivity and limitation of jaw motion .