We have studied MR images and the histopathology of eight patients with symptomatic Rathke's cleft cysts. Six cases showed visual disturbance and two showed galactorrhea. In five, the cyst fluid had low signal intensity on T1-weighted images and high intensity on T2-weighted images; in 2, the cyst fluid had high intensity on both T1 and T2-weighted images; in 1, the cyst fluid had high intensity on T1-weighted images and low intensity on T2-weighted images. Enhancement of the cyst wall by Gd-DTPA was able to be distinguished in six cases: two patients showed no enhancement, two showed thin enhancement and the remaining two, thick enhancement. Fluid aspiration and total resection of the cyst wall was performed in all patients (three cases by the transcranial approach and five by the transsphenoidal approach). Normal pituitary glands were found in all cases during the operations. Histopathologically, ciliated epithelium with goblet cells was recognized in three cases. Non-ciliated epithelium was recognized in the other five. Stratified squamous component was recognized in one case and secondary inflammation, in another. Normal pituitary tissue was recognized in five cases. Immunohistochemically, ciliated and non-ciliated epithelium was successfully stained for detecting antibody against epithelial membrane antigen and/or carcinoembryonic antigen. Two cases with no enhancement of the cyst wall by Gd-DTPA showed only ciliated epithelium. Two cases with thin enhancement of the cyst wall had single layer epithelium with normal pituitary tissue. Two cases with thick enhancement of the cyst wall showed single layer epithelium with its stratified squamous component or with secondary inflammation. A close relationship was suggested between the enhancement effect on MRI and histopathology of the cyst wall.