During treatment of multi drug resistant tuberculosis (MDR-TB), patients suffer from many adverse effects. Severe adverse effects may lead to refusal and discontinuation of treatment. Though national tuberculosis control programs are generally well structured, they do not collect information on adverse effects of drug directly. This study had been designed to observe the pattern of adverse effects of MDR-TB drugs in Bangladesh. This observational and descriptive type of longitudinal study was carried out at the in-patient department of the National Institute for Diseases of the Chest and Hospital, Dhaka, Bangladesh. The total number of subjects included was 64. The data collection was carried out with pretested questionnaire. After the interview at the initial stage, the respondents had to take part in interview again at one month interval up to the end of the 3^rd month of treatment. The collected data was analyzed in terms of descriptive method. The mean age of respondents was 34.76 ± 12.98 years. 20-60 years age group comprised80% of respondents. Male to female ratio was 2:1. Regarding the adverse effects of MDR-TB drugs, 80% of respondents suffered from arthralgia, 59% from anorexia, 52% from dizziness, 44% from nausea/vomiting and 44% from sleep disturbances. Gastritis, hypothyroidism and psychological disorders were each observed in 19% of patients. 17% developed impaired hearing. Peripheral neuropathy was developed by 28% of respondents. Serum creatinine level was raised in 3% of respondents. Hypocalcemia had been developed in 6% of respondents. Among psychological disorders, 67% consisted of depression, 25% were anxiety, and 8% were psychosis. The mean number of adverse effects that the respondents had to suffer from was 5 (range 1 -11).  Uninterrupted treatment had been continued in 86% of cases. Drug dose had to be reduced in 11% of cases and drug had to be stopped in 3% of cases. The findings of this study may provide baseline information in Bangladesh on adverse effects of MDR-TB drugs. The information may help minimizing the treatment interruption and thus preventing propagation and dissemination of MDR-TB.