High dental morbidity, especially inflammatory periodontal diseases, is aggravated by patients' fear of treatment even with the use of modern methods of anesthesia that leads to stress reactions and homeostasis damage. The aim of the study was to assess the level of anxiety in patients with chronic inflammatory periodontal diseases at the stages of dental treatment.Materials and methods. Sixty patients with chronic inflammatory periodontal diseases (CIPD) those were divided into four groups depending on the diagnosis were involved in the research. The level of reactive and personal anxiety was examined using the Spielberger-Khanin questionnaire. Results. It was found that the anxiety level varies depending on the disease severity, the treatment stage and the patient's gender. The highest rates of reactive anxiety were found in men during the initial treatment of moderate periodontitis and during severe periodontitis treatment. Women were characterized by an early increase in personal anxiety, but they demonstrated greater psycho-emotional stability during the treatment in comparance with men. Critical treatment stages those require pharmacological and other methods of correction of psycho-emotional state of patients with chronic inflammatory periodontal diseases were identified to improve the effectiveness of treatment.