Introduction: A direct smear microscopy is a universal tool used for the diagnosis of tuberculosis under programmatic settings. Early diagnosis of TB is crucial both clinically and epidemiologically. It is essential to ensure proper and early identification of cases, and good treatment outcomes to be able to limit its transmission and obtain successful TB control especially in low-income countries. The study aims to evaluate the efficacy of smear microscopy performed on post-NaLC__ampersandsignndash;NaOH decontaminated samples in the diagnosis of Tuberculosis. Materials and Methods: The samples were subjected to direct smear microscopy using Ziehl-Neelson (ZN) stain followed by decontamination and concentration by NALC-NaOH method and culture on Lowenstein Jensen media as well as in MGIT 960 system. Results of direct smear microscopy and post decontamination smear microscopy were compared against culture as the gold standard. Results: A total 705 samples were processed of which 658 were negative for acid-fast bacilli by direct microscopy. We observed that direct microscopy showed 41.22% (47) positivity whereas microscopy by post decontamination showed 60.52% (69) positive. A true diagnostic yield of 24% was obtained by post decontamination smear microscopy over direct microscopy.The overall sensitivity, specificity, PPV and NPV for direct and post decontamination smear was calculated as 36.84%, 99.15%, 89.36%, 89.06% and 60.52%, 97.96%, 85.19%, 92.79% respectively.Thus, the sensitivity of detection was increased by 23.68% on post decontamination smear microscopy with a diagnostic accuracy of 91.91%. Conclusion: Post decontamination smears showed a significant increase in diagnostic yield as compared to direct smear microscopy. Performing and reporting PDSM on samples requested for culture, as an additional step, inappropriate laboratory settings can have a greater impact in providing rapid and accurate diagnosis especially in smear-negative and extra-pulmonary TB cases.