In a prospective randomized comparative study of two groups of patients with chronic chlamydial urethritis complicated by prostatitis, treatment with azithromycin (comparison group) and azithromycin in combination with tilorone (main group) was performed. Combinations of two drugs was more effective (by 26.7 %, p<0.05) in etiological treatment, regression of pain syndrome assessed by NIH-CPSI scale (by 16.7 %), in dynamics of the total score of chronic prostatitis (13.3 %). In the main group the average value of INF-α was lower in 1.7 times, the INF-β - in 6.3 times, INF-γ - in 3.2 times. The data obtained indicate the benefits of azithromycin with tilorone combination in patients with chronic chlamydial urethritis complicated by prostatitis.