목적: Obstructive sleep apnea is characterized by symptoms such as daytime sleepiness, fatigue, snoring, choking and gasping in sleep and frequent arousal during sleep. Treatment of obstructive sleep apnea is based on the apnea-hypopnea index measured by polysomnography and possibility of correction for structural abnormalities. In practice, however, patients who visit the hospital most common complain of snoring and they are interested in reduction of snoring as well as improvement of AHI. The aim of this study was to evaluate the effect of upper airway surgery on snoring and AHI in adult patients with obstructive sleep apnea. 방법:From 2005 to 2015, 104 patients who visited our hospital with snoring and diagnosed with obstructive sleep apnea were treated with upper airway surgery. All of them measured objective snoring (%, duration) and subjective snoring scale through the polysomnography and questionnaire before and 3 months after surgery. 결과:After surgical treatment, the degree of objective snoring tended to decrease, but this was not statistically significant(p = 0.24). When the groups were classified according to the severity of obstructive sleep apnea, the degree of objective snoring in the mild and moderate obstructive sleep apnea group was significantly decreased(p = 0.02, p = 0.01). In the severe obstructive sleep apnea group, snoring increased after surgery, but this was not statistically significant(p = 0.32). In addition, as the initial apnea-hypopnea index was higher, the improvement of snoring tended to decrease(r = -0.35, p = 0.00). Subjective snoring scale (symptom) decreased significantly after the surgery(p = 0.00), which showed the same result in all three groups of obstructive sleep apnea(p =0.03, p =0.00, p =0.00). In addition, the change of snoring according to the type of surgery was not significant(p = 0.75), and the change of snoring according to the result of surgery was only significant in the cure group(p = 0.00). 결론:In patients with obstructive sleep apnea, surgical treatment may be thought to play a role in alleviating the disease by reducing the apnea-hypopnea index even though it does not cure obstructive sleep apnea. However, in terms of snoring, patients with mild or moderate obstructive sleep apnea improve snoring, but patients with severe obstructive sleep apnea tend to worsen snoring after surgery. Therefore, it is necessary to recognize and explain this fact when considering the upper airway surgery.