Introduction: Tuberculosis is an emerging and reemerging disease and standard tre-atments are used to control this disease all around the world these days. If TB trea-tment side effects are not early diagnosed, these side effects can be costly and very dangerous. The aim of this study was the assessment of TB treatment side effects and its determining factors.
 Materials & Methods: This study is desc-riptive-analytical and cross-sectional. Do-cuments of all patients diagnosed with TB were used from the beginning of April 2005 to the end of the September 2012 in Kh-uzestan province. The instruments for data collection included a checklist and demo-graphic variables for collecting the required data. The collected data was analyzed thr-ough SPSS-16 software by Chi-square, Ind-ependent t and Kruskal-Wallis tests.
 Findings: The overall 6363 TB patients with the mean age of 18±39.3 years were identified and studied. Side effects in 106 (1.66%) patients were associated with TB treatment during the treatment period. The most common complication was Hepatitis in 52 cases (49.05%). Side effects incidence had a significant relationship with gender, kind of disease, HIV infection, and result of chest radiography (P˂0.05).
Discussion &Conclusion: High incidence of complications in TB treatment among patients with over 65 years age and less than 4 years age and HIV infection cause disorder in TB controlling. Thus, training and protective measures and periodical as-sessment is recommended.