Aim. To study the prognostic value of syncope in non-massive pulmonary embolism (PE). Material and methods. Patients (n=64; 35 men and 29 women; aged 52±13 years) with non-massive PE were examined. 13 (20%) patients had a high risk of death according to the ESC criteria, and 51 (80%) — an intermediate risk. PE diagnosis was verified by X-ray contrast angiography or computer angiography of the pulmonary artery. Patients were split into 2 groups: patients of group 1 (n=14) had syncope episodes during the last 24 hours (from 1 to 30), and group 2 (n=50) — did not have. Groups did not differ by age, sex and disease duration. Comparative analysis of clinical and instrumental data, hospital mortality was made. Results. The significant differences for most parameters in the studied groups were not found. Combination of syncope and right bundle branch block on ECG was observed more often in PE patients of high risk mortality: 50% vs 14.2% in groups 1 and 2, respectively (p=0.004). High risk of death was defined 3 times more often in group 1 than this in group 2: 42.8% vs 14% (p=0.017). Syncope at the onset of non-massive PE clinical manifestations associated with more often hypotension development — 42.8% vs 14% in groups 1 and 2, respectively (p=0.017). Patients of group 1 needed in thrombolytic therapy 3 times more often than patients of group 2: 50% vs 16%, respectively. Hospital mortality did not differ significantly — 0 and 2% in groups 1 and 2, respectively. Conclusion. Syncope in non-massive PE, especially in combination with right bundle branch block on ECG, may be considered as a possible criterion for high risk of complications and can be rationale for thrombolytic therapy in addition to standard therapy. Designed studies on prognostic significance of syncope in PE, depending on mass of pulmonary artery lesions and risk stratification are necessary.