RationaleMulti-drug-resistant tuberculosis (MDR-TB) poses a significant public health challenge to the control and successful eradication of TB globally. Suboptimal treatment outcomes are common among persons with MDR-TB necessitating a need to understand the contextual factors. ObjectiveWe determined the factors associated with unsuccessful TB treatment among persons with MDR-TB at a large TB Unit in Central Uganda. MethodsWe retrospectively reviewed medical records for all persons with MDR-TB at Mubende Regional Referral Hospital MDR-TB Clinic in Central Uganda. The patients were treated with either second-line, modified second-line, or individualized anti-TB regimens and completed treatment between January 2012 and October 2023. The primary outcome was unsuccessful TB treatment defined as death, treatment failure, or loss to follow-up and measured as a binary outcome. We used a multivariable binary logistic regression analysis to determine the factors independently associated with unsuccessful TB treatment at a 5 % statistical significance level. We reported the adjusted odds ratio (aOR) and the 95 % confidence interval (CI). Measurements and resultsWe analyzed data from 98 persons with MDR-TB who were aged 15–78 years (mean 36.4 ± 15.4 years). Of these, 40 (40.8 %) were cured, 25 (25.5 %) completed TB treatment, 1 (1.0 %) had treatment failure, 13 (13.3 %) died, and 19 (19.4 %) were lost to follow-up. Overall, 33 (33.7 %) participants had unsuccessful TB treatment which was associated with older age for a 1-year increase in age (aOR 1.05, 95 % CI 1.01–1.09), malnutrition—mid-upper arm circumference of <12.5 cm (aOR 2.99, 95 % CI 1.16–7.98), and previous TB treatment (aOR 0.28, 95 % CI 0.10–0.77). ConclusionUnsuccessful TB treatment is high among persons with MDR-TB at this TB Unit. It is more likely as age advances and when persons with MDR-TB have malnutrition, but less likely when they have been previously treated for TB. Therefore, interventions to improve treatment outcomes may be beneficial for persons with MDR-TB who are older, malnourished, and those newly diagnosed with the disease. For example, routine nutritional assessment and counseling, including nutritional support for malnourished persons with MDR-TB may be needed to optimize their TB treatment success.