In a 5-month-old boy with a history of horizontal nystagmus and vomiting, computed tomography and magnetic resonance imaging (MRI) demonstrated bilateral subdural hygroma and contrast-enhanced lesions in the suprasellar region, medulla oblongata, and the spinal axis. Histopathological examination of a suprasellar tumor biopsy specimen revealed a World Health Organization (WHO) grade I desmoplastic infantile astrocytoma (DIA). A regimen of vincristine and carboplatin (VC) chemotherapy for low-grade astrocytoma was started. The tumor size immediately decreased, and the metastatic lesions also disappeared after the initial 10 weeks of chemotherapy. Although a residual tumor remained in the suprasellar region, no tumor regrowth was detected 13 months after finishing the chemotherapy. The patient showed no symptoms or developmental delay. Although surgical resection is the recommended therapy for symptomatic DIA, our experience suggests that VC chemotherapy might be a therapeutic option for DIA in infants with unresectable tumor or multiple metastasis.