Malignant biliary obstruction is a challenging problem for cancer patients. Here we evaluate predictive factors for survival following percutaneous drainage for malignant biliary obstruction in patients in whom endoscopic drainage was unsuccessful or insufficient. A retrospective register study in a tertiary-level university hospital. A total of 643 cancer patients (317 females and 326 males) with malignant biliary obstruction were treated with percutaneous drainage at our hospital between 1999 and 2016. Their median overall survival rate was 2.6months, with a 95% confidence interval (CI) of 2.2-3.0. Independent factors predicting poor outcome were metastatic cancer, with a hazard ratio (HR) of 2.2 (95% CI 1.8-2.7); Eastern Cooperative Oncology Group performance status (ECOG PS) of 2 (HR 2.3; 95% CI 1.8-2.8); ECOG PS of 3-4 (HR 3.5; 95% CI 2.8-4.4), American Society of Anesthesiologists physical status classification (ASA) of 4 (HR 2.1; 95% CI 1.5-2.9); and bilirubin of ≥60.0µmol/L within 30days post-drainage (HR 1.3; 95% CI 1.1-1.6). During the time periods 1999-2004 and 2005-2010, patients had poorer outcomes (HR 1.4; 95% CI 1.1-1.7 and HR 1.4; 95% CI 1.2-1.8) than during the last period 2011-2016. Patients with cancer who underwent percutaneous biliary drainage for biliary obstruction had a poor median overall survival. The usefulness of biliary drainage, especially in patients with metastatic cancer, poor ECOG PS, and high ASA class, should be critically considered.