Primary intracranial fibrosarcomas (PIFs) are extremely rare and the origin of these tumors is still controversial. The rarity of primary intracranial fibrosarcomas makes it difficult to diagnose them correctly and establish a standard treatment. The pathologic diagnosis is made by distinguishing findings from light microscopic and immunohistochemistry analysis. PIFs have been known to be very aggressive neoplasms. The extra-axial location of the tumor could provide an opportunity to perform a total resection even if it does not mean a cure. We present a case of PIFs mimicking a falx meningioma in a 17-year-old man.