Giant cavernomas (GC) are rare lesions, with less than 50 cases reported so far. Clinical presentation usually involves epileptic seizures and less typically focal neurological deficit, due to repeated hemorrhages and GC mass effect and consequentially increased intracranial pressure. Although individual cases have been reported, due to the rarity and variable imaging appearance, GCs are usually not considered in the differential diagnosis of large hemorrhagic lesions, especially when significant mass effect is present. A 17-year-old boy presented due to severe headache, right-sided weakness, and slurred speech. Symptoms started three days before with occasional headaches, which intensified gradually. Emergency computed tomography revealed a left frontal massive heterogeneous lesion. Soon after, right-sided hemiparesis and speech impairment progressed, and the patient became drowsy with the slightly dilated left pupil. Emergency surgery was performed, and the lobed grayish lesion was entirely removed. Based on the macroscopic appearance, the surgeon assumed it was a metastasis of melanoma. Histopathologic analysis result was cavernoma. GC should be considered as an option in hemorrhagic lesions, especially in the young age population. Emergency surgery for mass lesions is not uncommon in neurosurgery; however, bleeding cavernomas are usually planned for elective surgery due to the specific approach and complications.