To observe the differences in psychological status between Bell's palsy (BP) patients and healthy subjects, and to examine the relationship between psychological factors and the severity of BP, we conducted a case-control, multi-center clinical investigation. A total of 695 subjects were assigned to the case group (n=355) and the control group (n=340). House-Brackmann grading system and Facial Disability Index (FDI) were adopted to assess the BP patients; Kessler Psychological Distress Scale (K10) and 16 Personality Factor (16PF) scale were employed to evaluate the psychological distress and personality profiles of all subjects. Two independent samples t test was used to compare the differences between cases and controls, and to compare the differences among different BP patients. Pearson correlation analysis was used to examine the relationship between psychological factors and severity of facial paralysis. The results showed that psychological distress (K10) in case group (27.09 +/- 5.80) was significantly higher than that in control group (13.43 +/- 3.02) (t=-37.219, P=0.000). The scores of personality factor Warmth (A), Openness to Change (Q1), Self-Reliance (Q2) were lower in cases than in the controls (P < 0.01, P < 0.05, P < 0.05, respectively), whereas the scores of Sensitivity (I), Vigilance (L), Apprehension (O), and Tension (Q4) were significantly higher in cases than in the controls (P < 0.05, P < 0.01, P < 0.01, P < 0.01, respectively). In addition, the psychological distress was significantly higher in female patients, severe (HB score IV-VI) patients, and subacute (onset time 72-168 h) patients compared with that in male patients, mild (HB score I-III)patients, and acute (onset timea (c) 1/272 h) patients (P < 0.05). The scores of personality factor in female patients, severe patients, and subacute patients were also significantly different from male patients, mild patients, and acute patients (P < 0.05). The result of Pearson correlation analysis showed that psychological factors (K10, personality A, F, L, N, O, Q4) were closely related to HB scores. We are led to conclude that the psychological status between BP patients and healthy people are different; psychological distress and personality factors are closely associated with severity of facial paralysis.