Background: Postoperative sore throat is a complaint after general anesthesia of multifactorial etiology. The laryngeal mask airway (LMA) reduces sore throat and discomfort during maintenance of the airway and make patients more comfortable. The purpose of this study was to compare effect of patient's position during operation on postoperative sore throat after the use of LMA. Methods: The fifty three patients were randomly divided into two groups. Group 1 (n=30) was underwent general anesthesia with supine position and group 2 (n=23) with prone position. After the LMA was positioned in the hypopharynx and the cuff inflated, fiberoptic laryngoscope was immediately passed down through the LMA. Number of attempts, degree of postoperative sore throat and other complications were also noted. Results: The incidence of postoperative sore throat after the use of LMA was 10% in supine position and 4% in prone position. But the difference between the groups was not statistically significant. All of the reported sore throats were rated as mild. Conclusions: Postoperative sore throat after the use of LMA is mild and the incidence is not affected by the prone position during the operation.