Purpose: Analysis of new cases of pulmonary tuberculosis (PTB) with severe evolution. Materials & Methods: 99 new cases of PTB (extensive and complicated processes) were assessed. Results: PTB with severe evolution was detected in 76 (76,8%) men and 23 (23,2%) women. Of them 38 (38,4%) and 22 (22,2%) patients, respectively were transferred from therapeutic hospitals and admitted by MES. Slow onset of PTB (more than 3 months) and the acute one were observed in 96,9% and 3,1% patients, respectively. Infiltrative PTB was diagnosed in 83,8% patients (all cases being with destruction), сaseous pneumonia - in 16,8% patients, disseminated PTB – in 9,0% patients and generalized TB - in 5,0% patients. Revealed complications: pleural effusion - in 27,3% patients, hemoptysis - in 26,3 % patients, pneumothorax – in 2,0% patients. Epidemiological riskcontact with TB patients - happened in 14,1% cases, of which 7,0% were death cases; 13,1% patients had contacts in prison. Medico-biological factors were established as follows: gastrointestinal pathology, liver diseases, HIV infection, diabetes – in 25,3 %, 18,1%, 15,1% and 7,1% patients, respectively. Social factors with increased risk were: alcohol abuse, migrants, no permanent residence – in 29,3 % 17,1% and 9,1% patients, respectively. Combination of several risk factors was showed by 59,2 % patients. Sputum smears detected AFB in 49,5% patients. Culture positive state was observed in 93 % patients. Death occurred in 29,3% patients. MDR TB was established in 18,2 % patients. Conclusions: 1. PTB with severe evolution represents serious epidemiological (infectious) issue (the most of the cases are contagious forms). 2. Severe evolution of PTB occurred due to unsatisfactory monitoring of high risk groups having immunosuppression. 3. No vigilance for TB among population although clinical sings are present long before diagnosis.