Objective To analyze the facial feature indexes related to difficult visual laryngoscopic glottis exposure.Methods A total of 537 patients who underwent craniomaxillofacial surgery and tracheal intubation under general anesthesia were recruited from Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine from Aug. to Oct. 2020, with American Society of Anesthesiologists (ASA) grade Ⅰ-Ⅱ. The age, gender, height, weight and body mass index (BMI) of patients were obtained before anesthesia, and the photographs of patients in frontal neutral position, mouth opening with tongue extending position and head-up position were collected to quantify labeled facial features. When anesthesiologists performed tracheal intubation with a unified visual laryngoscope, the Cormack-Lehane (C-L) grade was recorded by the statistician. Subjects were assigned to easy visual laryngoscopic glottis exposure group (C-L grade Ⅰ-Ⅱ) or difficult visual laryngoscopic glottis exposure group (C-L grade Ⅲ-Ⅳ) according to the C-L grade. Subjects in the difficult group were matched 1:1 with those in the easy group based on age (difference of no more than 2 years) and gender. The facial feature indexes of the 2 groups were analyzed with the real results of visual laryngoscopic glottis exposure by multivariate logistic regression analysis to summarize the positive indexes useful for assessment.Results Thirty-one pairs of subjects were successfully matched with an age ranged from 15 to 75 years. The age of the difficult group and easy group was (49.29±17.47) and (49.23±17.47) years, respectively, and there was no significant difference in BMI between the 2 groups ([22.18±3.55] kg/m² vs[23.33±3.06] kg/m², P>0.05). For the facial features, the proportion of the distance from brow to nasal tip to the distance from the apex of the coronal surface of the frontal scale to the chin and the restriction of tongue extension were significantly different between the 2 groups (both P < 0.01). Multivariate logistic regression analysis found that the proportion of the distance from brow to nasal tip to the distance from the apex of the coronal surface of the frontal scale to the chin was significantly related to difficult laryngoscopic exposure (odds ratio[OR]=1.25, 95% confidence interval[CI] 1.02-1.53, P < 0.05).Conclusion Patients who have difficulty in glottic exposure with visual laryngoscope have some facial features that are different from easy exposure patients. They are more likely to have facial features with an increased proportion of brow to tip distance.