Objective To study the laws of TCM syndromes of sleep apnea syndrome （SAS） to provide evidence for treatment.Methods A survey-based

cross-sectional descriptive study was carried out on 80 patients with SAS diagnosed by overnight polysomnography.The questionnaire contained sociodemographic and clinical items and evaluation for symptoms of TCM.Results Of 80 patients

phlegm-damp was the most common syndrome

61 cases

76.25%

followed by blood stasis

34 cases

42.50%.The tongue was pale and dark red

enlarged with tooth prints and curved veins

and with sticky coating.In mild cases

38（90.5%） were of phlegm-damp syndrome

indicating that the mild cases were mainly of phlegm-damp syndrome and the moderate and severe cases mainly of deficiency with stasis.Conclusion SAS is mainly of deficiency complicated with excess

phlegm-damp and blood stasis are common syndromes

the mild cases were mainly of phlegm-damp

the moderate cases mainly of combination of phlegm with stasis

and the severe cases mainly of stasis.