Introduction. Chronic inflammation of the urinary bladder (CIB) is a disease entity which mostly concerns young women and which is connected with their short urether and vicinity of vagina sexual activity. Frequent recidication, in spite of use of new generation of antibiotics - often of considerable cost - have a significant influence upon life of the patients. Side-effects connected with frequent use of antibiotics are also an important factor to consider.<br /> Aim. The life discomfort of the patients, frequently low effectiveness and side-effects of antibiotherapy, numerous cases of recidivation were the reasons of application of medical ozone in chronic inflammation of the urinary bladder.<br /> Material and method. During 18 months oxygen-ozone mixture was applied directly to the blader in case of 72 patients, to 65 women, that is 90% of patients, and to 7 men, that is 10% of patients. The age group was 19 to 67, with the average age of 36. In case of men, the age group was from 38 to 51, with the average age of 44. The number of procedures, depending both on bacteriological results and subjective symptoms, veried from 10 to 18. Ecery patient, prior to the ozonotherapy underwent general urine analysis and bacteriological tests; also subjective symptoms as pollysis and bacteriological tests; also subjective symptoms as pollakiuria, pain and burning during miction, and pressing tenesmus were estimated, according to QL life comfort scale.<br /> Those tests were repeated three and six months after the ozonotherapy procedures.<br /> Results. In the women group (in all cases) statistically significant improvement of life comfort was noted. Results of bacteriological tests after one month and three months were germ-free, after six months bacteriological results of 4 patients, that is 6% showed initial results with relapse of subjective symptoms. Which are statistically significant improvement in the case of remaining 47 patients, that is 72% germ-free culture were gained and lack of subjective symptoms. In the 6 patients (that is 86%) men group, after six months, in all cases germ-free-culture and lack of subjective symptoms were gained.<br /> Conclusion. Application of ozonotherapy in treatment of chronic inflammation of the vladder is a of significant statistical effectiveness method, and what is more cheap and with low risk in performance.