We present a rare case of optochiasmatic cavernous angioma (CA) that progressed despite radiation therapy. A 31-year-old female patient presented with sudden loss of left visual acuity and right homonymous hemianopsia. Magnetic resonance imaging (MRI) revealed a suprasellar mass and findings compatible with a craniopharyngioma or an optic glioma with bleeding. An open biopsy was conducted using the transcranial approach, and histological examination revealed gliosis. During the one-year follow-up period, imaging suggested intratumoral bleeding and the mass continued to grow. We recommended re-operation, but the patient refused due to fear of surgery. Consequently, the patient received fractionated radiation therapy (3,000 cGy) to the parasellar area. Despite the radiotherapy, the mass continued to grow for the following 6 years. The final MRI before definitive treatment revealed a multi lobulated, multistage hematoma with calcification in the parasellar area, extending into the third ventricle and midbrain. The patient ultimately underwent reoperation due to the growth of the tumor. The mass was completely removed with transcranial surgery, and the pathologic findings indicated a cavernous angioma (CA) without evidence of glioma. As shown in our case, patients may suffer intratumoral hemorrhage after biopsy and radiotherapy. This case places the value of biopsy and radiotherapy for a remnant lesion into question. It also shows that reaching the correct diagnosis is critical, and complete surgical removal is the treatment of choice.