Intracranial aneurysms in children account for 4%-5% of all cases, with 20% being considered giant (>25 mm). The main sites of occurrence are the internal carotid artery (ICA) and the middle cerebral artery (MCA). Rupture and secondary subarachnoid hemorrhage occur in approximately 55%-72.5% of cases, with a 10%-23% mortality rate. We report the case of a previously healthy nine-year-old girl who developed sudden, severe right retroocular pain and a holocranial headache as a mode of onset. Besides, the patient presented with double vision, and her relatives sought medical attention. Paresis of the right III, IV, and VI cranial nerves was found at physical examination. An MRI and digital subtraction angiography showed the presence of a giant aneurysm in the cavernous portion of the ICA with a mass effect. The patient was treated surgically through a high-flow bypass using a radial artery graft and trapping of the aneurysm. She had an uneventful postoperative course and was discharged three days after the operation to continue follow-up at the outpatient clinic. The therapeutic options were: a) an endovascular approach using flow diverters or stenting and coiling; or b) surgical treatment with proximal closure of the ICA if the patient had good collateral circulation or trapping the aneurysm combined with a high-flow bypass if the collateral circulation was not good or absent. After discussion, we decided on the surgical option. Even when the surgery was successful in this case, there is no consensus about the best way to treat it; the selection should be based on the center´s experience when confronting this rare entity.