Background: In India, 15% of pulmonary tuberculosis cases have been estimated to be attributable to DM. Clinical presentation of Tuberculosis and Diabetes is overlapping many times, difficult to differentiate one from other. Although DM has been associated with increased risk of TB treatment failure or relapse, and diminished 2-month and 6-month culture conversion rates, neither international guidelines nor India’s Revised National TB Control Programme (RNTCP) currently recommend active screening of TB patients for detection of DM. Methods: Prospective study conducted at MIMSR Medical College Latur, India during Jan. 2011 to Nov. 2013 included 200 cases of TB with Diabetes Mellitus (DM), compared with 200 cases of TB without DM. Objectives of study were to correlate impact of DM on sputum conversion rate and on clinic-radiological pattern. Results: PTB was observed in 141 (70.5%) cases with DM as compared to 173 (86.5%) cases without DM, while EPTB was observed in 59 (29.5%) cases with DM as compared to 27 (13.5%) cases without DM (p<0.0002). Lower Lung fields involvement in 34 (24.11%) cases with DM and 11 (6.35%) cases without DM cases. Pulmonary Cavities were observed in 55 (39.00%) cases with DM and 49 (28.32%) cases without DM (p<0.0001). Sputum conversion at intensive phase completion was observed in 76.53% and 92.70% cases of PTB with and without DM respectively (p<0.003). Out of 5.2% cases which were failed to show sputum conversion in diabetic group, 2.8% cases were found to have MDR. Conclusion: DM affects the clinical, bacteriological and radiological presentation of PTB. Failure of sputum conversion after intensive phase completion should be interpreted cautiously, as many cases were showing sputum conversion after one month therapy of completion of intensive phase and only 2.8% cases found to have MDR.