This study aimed to evaluate the association between the preoperative Controlling Nutritional Status (CONUT) score, survival outcomes, and recurrence pattern in patients with resectable biliary tract cancer (BTC).A total of 224 BTC patients (gallbladder, n = 69; intrahepatic bile ducts, n = 26; perihilar bile ducts, n = 72; distal bile duct, n = 57) who underwent surgery with curative intent were enrolled. The best cutoff point of the preoperative CONUT score in discriminating survival was determined using χPatients were subdivided into the CONUT-low (score ≤ 3, n = 156) and the CONUT-high (score3; n = 68) groups. In-hospital mortality occurred more frequently in the CONUT-high group than in the CONUT-low group (7.4% vs. 1.3%; p = 0.028). A high preoperative CONUT score was independently associated with worse overall survival (hazard ratio [HR] 1.906, p = 0.001), worse disease-specific survival (HR 1.840, p = 0.006), and worse recurrence-free survival (HR 1.680, p = 0.005). Recurrence developed in 110 (49.1%) patients. A high preoperative CONUT score was independently associated with a higher risk of distant recurrence (HR 2.245, p = 0.001), but not locoregional recurrence. The incidences of distant recurrence at 5 years were 55.4% and 34.2% in the CONUT-high and CONUT-low groups, respectively (p = 0.001).The preoperative CONUT score independently predicts survival outcomes and may serve as a surrogate marker of aggressive systemic disease recurrence in patients with resectable BTC.