Thornwaldt's cyst results from the failure of regression of notochordal tissue in the posterior nasopharyngeal area. Trauma and subsequent inflammation of the defect lead to a complex of symptoms known as Thornwaldt's disease. Appropriate therapy which includes excision or marsupialization of the cyst will provide complete relief of the symptoms. We experienced a case of Thornwaldt's cyst which was developed in a 51 year old female patient. So, we report this case with brief review of the literature.