Paradoxical response (PR) is defined as a clinical or radiological worsening in patients receiving adequate anti-tuberculosis treatment, with the exclusion of documented relapse or of other disease presentations. Although most patients with PR show spontaneous improvement, some cases presenting with diffuse alveolar damage have also been reported.Retrospective clinical and laboratory data were collected on 89 patients of pulmonary tuberculosis who were treated at our hospital between April 2013 and January 2019.PR occurred in 21 patients (24%), and the median onset time after anti-tuberculosis treatment was 22 days. The time to onset of PR was shorter in diffuse pulmonary infiltrates group than in local pulmonary infiltrates group or in pleural effusion group. Low serum albumin, elevated lactate dehydrogenase (LDH), high Creactive protein (CRP) and chest radiographic appearance exceeding one-lung area were associated with PR incidence. There was no difference in sputum smear grading and pulmonary cavitation. Six out of the ten patients died, developing PR with diffuse pulmonary infiltrates.Low albumin and chest radiographic appearance exceeding one-lung area were risk factors for developing PR. Diffuse pulmonary infiltrates in early phase of anti-tuberculosis treatment was related with Inhospital mortality.