Background: As to the profile of adverse drug reactions (ADRs) due to directly observed treatment, short course (DOTS), there is no report available in patients receiving antituberculosis (anti-TB) chemotherapy in Manipur, India. One of the main reasons for non-adherence to anti-TB therapy (ATT) is ADRs, even under DOTS. Aims: This study aimed to determine the incidence of ADRs due to DOTS therapy with a TB population of Manipur, India. Setting and Design: A prospective institution-based cohort study, and performed during July 2009-December 2010. Materials and Methods: The study included 102 diagnosed TB patients on anti-TB treatment under DOTS. Every patient was followed-up for the duration he/she received the treatment. Statistical Analysis: Frequency of different ADRs was assessed and p value was determined. Results: Incidence of TB was more among males than female (76.47% against 23.53%). Seventy-one patients (69.01%) showed one or more ADR. Incidence of ADRs based on affected organ was: Gastrointestinal (GI) disorders in 38 patients (53.52%), generalized weakness in 12 patients (16.9%), liver dysfunction in 11 patients (15.49%), allergic skin reactions in six patients (8.45%), neurological system disorders in two patients (2.82%), and fever in two patients (2.82%). However, 30.99% did not experience any ADRs. Conclusion: Incidence of ADRs due to DOTS therapy was 69.01%. Majority of cases suffered from GI symptoms. This highlighted the importance of developing strategies to ameliorate ADRs both to improve the quality of patient care and to control TB safely.