Anaemia predicts delayed sputum conversion and mortality in tuberculosis (TB). We determined the prevalence and factors associated with anaemia among people with TB at the National Tuberculosis Treatment Centre in Uganda. People with bacteriologically confirmed TB were consecutively enrolled in a cross-sectional study between August 2017 and March 2018. Blood samples were tested for a full blood hemogram, HIV infection, and CD4+ and CD8+ T-cell counts. Anaemia was defined as a haemoglobin level of < 13.0 grams per decilitre (g/dl) for males and < 12.0 g/dl for females. Of 358 participants, 210 (58.7%, [95% confidence interval (CI): 53.4 -63.8]) had anaemia. Anaemia was associated with night sweats, a longer duration of fever, low body mass index (BMI), hyperthermia, high sputum bacillary loads, HIV co-infection, and low CD4 and CD8 counts at bivariate analysis.Factors associated with anaemia at multivariable analysis were low BMI (odds ratio (OR) = 2.93, 95% confidence interval (CI) 1.70-5.05, p<0.001), low CD4:CD8 ratio (OR = 2.54, 95% CI 1.07-6.04, p = 0.035), and microcytosis (OR = 4.23, 95% CI 2.17-8.25, p<0.001).Anaemia may be associated with features of severe TB disease and should be considered in TB severity scores.