&NA;Intracranial epidermoid and dermoid tumors are unusual benign lesions that are potentially curable. Subtotal removal carries a high incidence of recurrence, plus the rare possibility of carcinomatous degeneration of the remnants. Aseptic meningitis from spillage of cyst contents into the subarachnoid space is frequent after operation and has been reported to occur spontaneously. A case of a patient with a posterior fossa epidermoid cyst presenting with multiple bouts of aseptic meningitis in which squamous cell carcinoma arose in recurrent tumor 5 years after subtotal removal of the benign lesion is described. (Neurosurgery24:574‐578, 1989)