BACKGROUND: Antituberculous therapy is set a short-term therpy used isoniazid(INH), rifampin(RFP), ethambutol(EMB), pyrazinamide(PZA) from 1970s' and treatment rate has been very improved. But drug interruption or irregular medication due to side effects and resistance of drug are serious problem to retreatment cases, specially. Ofloxasine(OFX), developed from Quinolone at 1980's is effective not only other respiratory infectious disease but also pulmonary tube rculosis. And this is useful drug instead of injection agents for retreatment patients who have side effects to other drugs, lived far distance from medical clinics. So, we will evaluate theffectiveness as four oral drags involving OFX. METHOD: A retrospective study was made through the regular follow up of smear positive cases,who treated by four drag, namely, prothionamide (PTA) cycloserine(CS), OFX, paraminosalicylic acid(PAS). RESULTS: 1) Out of 66case with positive sputum AFB smear, 42(64%)cases achieved the negative conversion. 2) Considering the negative conversion in all group, 34 case (52%) of sputum conversion occured within first 6 months, on the extent of diease was minimal, moderate, far advavanced pulmonary tuberculosis, sputum AFB smear negative response to treatment was 100%, 78% , 46% respectively. 3) The roentgenological improvement occured in 38(58%), extent of diease was minimal, moderately, far advanced pulmonary tuberculosis, Roentgenological improvement to retreatment was 75%, 64%, 46%. 4) When the duration of patients illness was less than 1 year, 1 to 3 years, 3 to 5 years and more than 5 years, sputum AFB smear negative response to retreatment was 100%, 88%, 80%, 52%. 5) On side effects, major problems are gastrointestinal troubles, mild liver function abnormality, psychotic problemes, and skin problem(urticaria, itching sensation). CONCLUSION: The duration & extents of patients illness was shorter & minimal, sputum AFB smear negative response rate was better. Radiologic response is better as shorter duration and minimal extent of diease. But, as diease is longer duration & far advanced, sputum negative conversion & Roentgenological improvement is poor and limited. The adverse reaction was mainly observed gastrointestinal troubles(indigestion, abdominal pain, nausea, vomiting, diarrhea) and are well controled by symptomatic management in most patients, as regard to tolerance to the secondary drugs.