Mycotic cerebral aneurysms in neonates are extremely rare and can be difficult to diagnose without a high index of suspicion. We describe a 33-week gestation preterm neonate who developed a mycotic cerebral aneurysm leading to death before repair could be performed. We believe this to be the first literature reported case of a mycotic cerebral aneurysm in a preterm infant. This case revives the ongoing question of when to perform a lumbar puncture in a potentially septic or meningitic infant, while also casting light on maintaining a high index of suspicion for rare intracranial diagnoses that require cranial imaging.