Hydranencephaly (HE) is a rare congenital brain disorder in which the cerebral hemispheres are absent and replaced by sacs filled with cerebrospinal fluid (CSF). This entity is rarely seen in postnatal life and has an incidence of less than 1 per 10,000 live births. This is a 5-day-old neonate brought in for a transfontanelle ultrasound scan (TFUS), referred from a peripheral health facility on account of relatively large head, sudden onset of fever, poor cry after birth and a low Apgar score. The TFUS was done through patent anterior and posterior fontanels in sagittal and axial planes and through the temporal bone interrogation. The TFUS demonstrated absence of the two cerebral hemispheres; these are replaced by hypoechoic fluid (CSF), the presence of an echogenic midline falx cerebri, the presence of the cerebella hemispheres and midbrain with normal morphological appearance. A diagnosis of hydranencephaly in a neonate (5-day-old) was established following the aforementioned findings from TFUS; the parents were advised to consult a neurosurgeon in a tertiary health facility for further expertise management. We report a case of 5-day-old neonate with TFUS findings conforming to Hydranencephaly due to its rare nature and peculiar presentation.