Cholangiocarcinoma (CC) is the second most common primary hepatic malignancy after hepatocellular cancer, accounting for 10–25% of all hepatobiliary malignancies. It is more prevalent in Asia than in Western countries, largely due to higher rates of established risk factors such as parasitic infections, bile-duct cysts, and hepatolithiasis. Established risk factors for CC include parasitic infections (e.g., Opisthorchis viverrini and Clonorchis sinensis), biliary-duct cysts, hepatolithiasis, and primary sclerosing cholangitis (PSC). Less-established risk factors include inflammatory bowel disease (IBD), hepatitis C virus (HCV), hepatitis B virus (HBV), cirrhosis, diabetes, obesity, alcohol consumption, smoking, and genetic polymorphisms. While some risk factors, such as HCV, are more strongly associated with intrahepatic cholangiocarcinoma (ICC) in Western countries, HBV is more commonly linked to ICC in Asian countries. Cirrhosis is a consistent risk factor for ICC but not ECC. The classification of CC into ICC and ECC is crucial for understanding risk factors, as some risk factors may have different effects depending on the site. Misclassification of CC, particularly of Klatskin tumors, can lead to inaccurate epidemiological data. Despite extensive research, there is limited consensus on the role of IBD, obesity, smoking, and specific genetic polymorphisms as independent risk factors for CC. Diabetes and heavy alcohol consumption may increase the risk of CC, while HCV is consistently associated with ICC in Western countries. The lack of a consistent classification system for CC complicates the interpretation of risk factors in epidemiological studies. Overall, CC is a rare malignancy in Western countries but more common in Asia, with established risk factors playing a significant role in its incidence.Cholangiocarcinoma (CC) is the second most common primary hepatic malignancy after hepatocellular cancer, accounting for 10–25% of all hepatobiliary malignancies. It is more prevalent in Asia than in Western countries, largely due to higher rates of established risk factors such as parasitic infections, bile-duct cysts, and hepatolithiasis. Established risk factors for CC include parasitic infections (e.g., Opisthorchis viverrini and Clonorchis sinensis), biliary-duct cysts, hepatolithiasis, and primary sclerosing cholangitis (PSC). Less-established risk factors include inflammatory bowel disease (IBD), hepatitis C virus (HCV), hepatitis B virus (HBV), cirrhosis, diabetes, obesity, alcohol consumption, smoking, and genetic polymorphisms. While some risk factors, such as HCV, are more strongly associated with intrahepatic cholangiocarcinoma (ICC) in Western countries, HBV is more commonly linked to ICC in Asian countries. Cirrhosis is a consistent risk factor for ICC but not ECC. The classification of CC into ICC and ECC is crucial for understanding risk factors, as some risk factors may have different effects depending on the site. Misclassification of CC, particularly of Klatskin tumors, can lead to inaccurate epidemiological data. Despite extensive research, there is limited consensus on the role of IBD, obesity, smoking, and specific genetic polymorphisms as independent risk factors for CC. Diabetes and heavy alcohol consumption may increase the risk of CC, while HCV is consistently associated with ICC in Western countries. The lack of a consistent classification system for CC complicates the interpretation of risk factors in epidemiological studies. Overall, CC is a rare malignancy in Western countries but more common in Asia, with established risk factors playing a significant role in its incidence.