Surgery is the only effective treatment able to improve survival of patients with hilar cholangiocarcinoma (CCA). However, the significance of prognostic factors on overall survival is still debated. We evaluated early and long-term outcomes of patients resected for hilar cholangiocarcinoma over a 3-year period to determine the role of prognostic factors and their effect on overall survival. Medical records of patients with hilar CCA who underwent resection between January 2001 and December 2004 were retrospectively reviewed. Univariate and multivariate analysis was performed to identify prognostic factors associated with survival. Thirty-two of 45 patients underwent surgical resection with curative intent. Morbidity was 24.4 per cent; perioperative mortality was 0 per cent. Overall median survival was 22.3 months. Well-differentiated tumor grading and R0 resection were independently associated with better survival at multivariate analysis. Aggressive surgery, including biliary resection combined with major hepatectomy, is a safe procedure with low morbidity and mortality in a tertiary referral hepatobiliary center. The main aim of an aggressive surgical approach is to obtain a microscopic margin-negative resection, which is associated with better prognosis. Another important prognostic factor is tumor grading, which is independently associated with survival.