Objective To explore the feasibility and application value of sonography in the evaluation of oropharynx in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods The oropharynx of forty-four patients with OSAHS and forty-four healthy subjects selected as the control group were separately examined by ultrasonography.The parameters including anterior-posterior diameter and the lateral diameter of oropharyngeal airway of the end-deep inspiratory and end-deep expiratory,thickness and wide of tongue base,lingual wide,lingual height,distance from mandibular plane to hyoid bone and distance from tongue base to mandibular plane were obtained for statistical analysis and compared between the two groups.Correlation analysis of above parameters plane with body mass index (BMI) were carried out. Results The anatomy of the oropharynx was well shown on sonography.When compared with the control group,the lateral diameter of oropharyngeal airway,thickness of tongue base,lingual height,lingual wide and distance from mandibular plane to hyoid bone also showed significant statistically differences between the OSAHS patients group and the control group (all P <0.01).The wide of tongue base,thickness of tongue base,lingual wide,lingual height,distance from mandibular plane to hyoid bone,and distance from tongue base to mandibular plane in OSAHS patients group were positively correlated with BMI( r =0.533,0.415, 0.555,0.349,0.378,0.419;all P <0.05).The wide of tongue base and lateral diameter of oropharyngeal airway in the control group were negatively correlated with BMI ( r = -0.324,-0.405,-0.317;all P <0.05).Conclusions Ultrasonography can be used to assist in the assessment of OSAHS,which can provide an important reference for clinical diagnosis and therapeutic effect evaluation of OSAHS.