Primary intradiploic epidermoid cyst of the central nervous system (CNS) is a rare disease. More than 200 cases have been reported so far. The lesion can affect every flat bone of the cranium. The pre-operative diagnosis is always misleading. We reported a 61-year-old female with giant primary intradiploic epidermoid cyst in the parietal bone. Surgical resection was performed. The patient recovered well with no complication nor neurologic dysfunction. A literature review of the disease will also be presented here. .