BACKGROUND & AIMS: The nutritional status of people with human T-lymphotropic virus (HTLV-1) infection has been poorly described because it involves a neglected disease. The few studies that have been conducted mostly involve people with neurologic consequences and the possible clinical evolutions of the disease. The aim of this study was to describe the nutritional status of patients with HTLV-1, including those with associated myelopathy/tropical spastic paraparesis, and to evaluate food security in these patients. METHODS: A retrospective observational study was conducted in people with HTLV-1 admitted to a referral hospital. We collected data from 17 medical records, including anthropometric data (i.e., body mass index, mid-upper arm circumference, triceps skinfold, and mid-arm muscle circumference), laboratory test results (i.e., haemoglobin, haematocrit, albumin, globulin, iron fixation capacity, and iron), the Subjective Global Assessment (SGA) method, and food security (Brazilian Food Insecurity Scale) data. The data were analysed using the R-project software. To evaluate possible associations between the outcomes and predictors (age at hospitalisation, food security, presence of children <18 years of age living in the household, income, schooling, ANSG, BMI, difference between ideal weight and hospitalisation, TSF, MUAC ICU days, hospitalisation outcome, rehospitalisation in the first year after discharge, interval between readmissions, death, associated conditions, constipation upon admission), we used Kruskal-Wallis, Mann-Whitney, Fisher's exact, chi-square tests with continuity correction, and Spearman's correlation coefficient. Hypothesis tests were considered statistically significant when p ≤ 0.05. RESULTS: The mean age of the patients was 57 (52-60) years. The patients were predominantly women (59%) and had an income lower than the local minimum wage with at least 6 years of schooling (52.3%). Only 18.2% of patients were eutrophic according to their BMI and 23.5% of patients were malnourished based on the SGA method. Patients predominantly had food security (64.7%) and good intestinal functions (64.7%) during their hospital stay. CONCLUSION: Despite having a limited number of patients in this study, HTLV-1 patients admitted to hospital are at high risk of malnutrition based on the scores from the SGA method.