We investigated the efficacy of different biliary drainage methods for the treatment of unresectable cholangiocarcinomas. We performed a retrospective study of 28 patients with unresectable cholangiocarcinomas who underwent biliary drainage at our hospital between January 2008 and June 2014 to compare the incidence of post-drainage stent dysfunction (SD) and reintervention (RI) for SD according to primary drainage method, lesion site, and complication status (the presence or absence of cholangitis). The duration of stent patency was compared between the different stent types. No significant differences in the incidence of SD and RI were found according to primary drainage methods, lesion site, or the presence or absence of cholangitis. The mean durations of stent patency for plastic and metal stents were 2.7 months and 7.4 months, respectively, suggesting that metal stents should be selected when the estimated prognosis is ≥2 months. Furthermore, metal stent placement, rather than the additional placement of plastic stents, should be considered a feasible option in cases of SD.