Background. Sulodexide is a perspective drug for correction of objective and subjective symptoms of chronic venous disease (CVD). Therapy with oral sulodexide seems very convenient for outpatient treatment of CVD patients. Objective. To analyze the results of oral sulodexide therapy in patients with CVD C3—C4 in routine practice. Material and methods. We performed a subanalysis of data from the Russian multiple-center prospective observational study ALLEGRO. Characteristics of 14 symptoms and sings of CVD, percentage of patients with treatment adherence over 50%, satisfaction of patients and physicians with the treatment were estimated. Four- and five-point Likert scale was applied to analyze satisfaction with the treatment. The data were collected by using of the Russian Registry of Treatment of Chronic Venous Diseases (RRT CVD, ClinicalTrials.gov ID: NCT03035747), study ID in RRT CVD VRCVD 7.003. The cohort for subanalysis is divided into 3 groups according to the general dosage of the drug prescribed for the course of treatment with 1—2 capsules of 250 lipoprotein lipase units (LU) 1 or 2 times a day: 30,000 LU, 45,000—60,000 LU, more than 90,000 LU. Results. Oral sulodexide therapy was prescribed in 511 patients. Mean number of symptoms at inclusion was 6.3±3.1, at the 2nd visit — 5.4±3.1, at the 3rd visit — 3.7±2.9. Overall score of symptoms was 12.2±8.8, 7.5±6.4 and 4.3±4.0, respectively. Change of the total score of symptoms between the onset and the end of therapy depending on the total dosage was 5.8±5.3 for 30,000 LU, 5.3±2.4 for 45,000—60,000 LU, 10.4±5.2 for more than 90,000 LU. Compliance with the treatment (percentage of patients who received over 50% of the prescribed dose) was 84%, 100% and 96%, respectively. Satisfaction with the treatment was 99% and 98% in patients and physicians, respectively. This value ranged from 96% to 100% in subgroups divided by the total dosage of sulodexide. Conclusion. Oral sulodexide therapy in patients with CVD leads to significant reduction in the prevalence and severity of venous symptoms. Compliance to oral sulodexide treatment is high. Better results are associated with administration of higher doses of the drug.