Introduction: Multidrug-resistant Tuberculosis (MDR-TB) is caused by mycobacterium tuberculosis that is resistance to at least Isoniazid and Rifampicin, Second line drugs are usually associated with adverse events which may be intolerable especially during the intensive phase of treatment. In Tanzania the prevalence of new and retreatment cases is 1.1% and 3.9% respectively. Objective: To determine prevalence and risk factors for adverse events among MDR TB patients during the intensive phase of treatment. Methods: Analysis of secondary data of all 171 patients admitted and completed treatment of MDR TB at Kibong’oto national referral TB hospital between July 2010 to march 2014. Results: A total of 171 MDR TB patients who completed the intensive phase of treatment were reviewed where by males were 117 (68.4%) and females were 54 (31.6%). Following treatment initiation 2% defaulted, 9% died and 89% of patients completed successfully the intensive phase of treatment. The study found that 29% were HIV positive, 94% were previously treated for non- MDR-TB, 53% had history of cigarette smoking and 57% had history of alcohol drinking. Conclusion: Patients treated with second line medicines at Kibong’oto National Hospital experienced mild to moderate adverse events during the intensive phase of treatment. Most of these adverse events were tolerable for continuation of treatment, very few were life threatening which needed special attention. Keywords: Multi drug resistant tuberculosis, adverse events, risk factors, Kibong’oto Hospital.