The present study presents the case of a 66-year-old patient diagnosed with prostate adenocarcinoma 4 years earlier and treated with prostatectomy, radiotherapy, chemotherapy and hormone therapy but still displaying high prostate-specific antigen (PSA) levels. The patient complaints were double vision and headaches. Upon physical examination, he displayed 6th cranial nerve paresis and 5th cranial nerve paresthesia. A magnetic resonance imaging (MRI) exam was performed, which revealed a mass on the right trigeminal cave. The patient underwent surgical removal of the tumor, and the pathological analysis of the specimen established metastatic prostate cancer as the diagnosis.Brain metastases from prostate cancer are extremely rare and mark advanced disease, with immune system failure and blood-brain barrier breach. Prostate-specific antigen levels do not correlate with the possibility of metastatic disease. Prostate adenocarcinoma is the histologic type most commonly associated with brain metastases, with the meninges being more frequently affected, followed by the brain parenchyma. The neurological symptoms more often displayed are non-focal, such as headaches and mental confusion. Surgery associated with radiotherapy is the most validated treatment.