Sputum conversion is an important milestone in the management of pulmonary tuberculosis. Early sputum conversion is desirable. A controlled study was done to improve sputum conversion rate of current short course chemotherapy using immunomodulator containing mycobacterium w. The immunomodulator is very potent and freely available. It shares antigens with Mycobacterium tuberculosis. In a randomised pattern 69 of 134 patients suffering from pulmonary tuberculosis received the immunomodulator intradermally every 15 days along with chemotherapy. The use of the immunomodulator results in preponement of sputum conversion. The sputum conversion rate obtained by chemotherapy at 60 days was achieved latest by 30 days when mycobacterium w containing immunomodulator was used as an adjuvant therapy. This was found irrespective of bacterial load (1 +, minimal or 3+, maximal) in sputum or category (fresh or retreatment) of disease. The therapy was well tolerated.