Both dentists and patient are interested to know the complications following periodontal therapy. The purpose of this study was to document this incidence following periodontal therapy carried out in a postgraduate periodontal clinic at Damascus university, and to identify factors that influence postprocedural pain. 214 patients between 18 to 57 years of age, most of them women ( 57,94% ) enrolled in this study. Pain was reported by 51,86% of the patients, which means they needed analgesics after the first post operative day. Infections were present in only 4 patients, two of them were under antibiotics. Females experienced significantly more pain than males after periodontal treatment. Pain decreased significantly in patients over 45. Also smoking and prophylactic antibiotic reduced the incidence of postprocrdural pain. In this study , ther e were no correlation between pain and the following: periodontal dressing, systemic diseases, oral hygiene, types of periodontal surgery and extent of the surgery. Surgical periodontal treatment is more painful than non-surgical treatment, but even non-surgical therapy is painful sometimes. 29,72% of the non-surgical therapy patients experienced postprocedural pain. On the basis of this study ,it appears that minimal complications were associated with periodontal therapy.