Functional status linked to a poor outcome in a broad spectrum of medical disorders. Barthel Activities of Daily Life Index (BADLI) is one of the most extended tools to quantify functional dependence. Whether BADLI can help to predict outcomes in elderly patients with acute venous thromboembolism (VTE) is unknown. The current study aimed to ascertain the influence of BADLI on 6-month all-cause mortality in aged patients with VTE. This is a prospective observational study. We included consecutive patients older than 75-year-old with an acute VTE between April 2015 and April 2017. We analyzed several variables as mortality predictors, including BADLI-measured functional status. Afterward, we performed a multivariate analysis, using logistic regression, to identify all-cause mortality independent predictive factors. Two hundred and two subjects were included. Thirty-five (17%) patients died in the first 6 months. The leading cause of death was cancer (59%). After multivariable logistic regression, we identified BADLI and Charlson index as independent predictors for 6-months mortality BADLI (every decrease of 10 points) OR 1.21 95% CI (1.03–1.42) and Charlson index OR 1.71 95% CI (1.21–2.43). Body mass index (BMI) values were inversely related to mortality OR 0.85 95% CI (0.75–0.95). In conclusion, BADLI, BMI, and Charlson index scores are independent predictive factors for 6-month all-cause mortality in old patients with VTE.