Tuberculosis spreads by droplet infection. When a patient with pulmonary tuberculosis coughs, sneezes or talks bacilli may get disseminated to the environment. Sputum smear positive patients are more infectious due to higher bacillary load in them. Proper cough hygiene may reduce the transmission of tuberculosis. Aim of the study: To find the knowledge and practice of cough hygiene in smear positive pulmonary tuberculosis patients on treatment under RNTCP. Materials and Methods: This was a hospital based cross-sectional study conducted on patients attending the DOTS center in A J institute of medical sciences over a period of 1 year. Patients with smear positive Pulmonary Tuberculosis who were on DOTS were interviewed to assess their knowledge. Smear negative and extra-pulmonary tuberculosis patients, patients were excluded. All these patients were given a pre-formed questionnaire and were interviewed regarding their knowledge about pulmonary tuberculosis, the mode of spread and symptoms of pulmonary tuberculosis. Cough hygiene and method of sputum disposal was asked in detail. Results: Total of 150 respondents were included in the study of which females were 46 and males were104. Most of the respondents were less than 30 years of age. The education level of majority of the patients was elementary school. Majority of the respondents were aware that coughing is the mode of transmission. Majority were aware regarding the preventive measures for transmission (94%). Only a minority of the respondents (6%) were unaware of cough hygiene. Out of the 150 respondents, 149 patients (99.3%) demonstrated faulty coughing technique. Conclusion: Majority of the people in the study population had good knowledge regarding cough hygiene. Majority of the people demonstrated faulty coughing technique. Proper cough hygiene and coughing technique should be taught to all patients with pulmonary tuberculosis so as to reduce the risk of transmission of the disease. Further studies are needed to assess the role of anti-tussive medications as they reduce cough, may thereby reduce the transmission.