Primary ectopic meningiomas occurring in the mediastinal region are extremely rare. So far, only five cases of primary mediastinal meningioma have been reported in the literatures. The imaging characteristics and the clinicopathological significance of mediastinal psammomatous meningioma have not been detailed. Here, we report the case of a 42-year-old male with primary posterior mediastinal psammomatous meningioma. The clinical features, imaging, and pathological findings are carefully analyzed, and the relevant literatures were reviewed.