The unenhanced spin-echo T1-weighted images, contrast-enhanced (dynamic and conventional) T1-weighted images and spin-echo T2-weighted images of 19 patients with histologically proven intrahepatic cholangiocarcinoma were reviewed. The results showed that typical intrahepatic cholangiocarcinoma presented as a large mass of low signal intensity on T1-weighted images. On T2-weighted images tumours generally presented as high signal intensity masses. In five patients the tumours exhibited varying degrees of central hypointensity on T2-weighted images. On contrast-enhanced images, large tumours (diameter larger than 4 cm, n = 14) typically showed peripheral enhancement with delayed or incomplete central filling. This pattern was seen most commonly. Smaller tumours (diam. 2-4 cm, n = 5) typically exhibited homogenous enhancement. On dynamic studies, enhancement of the tumours showed a centripetal pattern. Complete enhancement was observed in the small tumours. Among the larger lesions central sparing of the tumours was seen. It is concluded that contrast-enhanced MR imaging is useful in the diagnosis of intrahepatic cholangiocarcinoma. The characteristic enhancing pattern of intrahepatic cholangiocarcinoma was seen less commonly in smaller tumours. Definite differentiation from other liver masses in this case could be less certain.