Arachnoid cysts are well known to the neurosurgeon, and the evolution of their surgical treatment has followed technological advances in neurosurgical procedures and techniques. With the recent mastering of neuroendoscopy by the neurosurgeons, it is becoming the modality of choice for the treatment of arachnoid cysts. A neonate harboring a middle parasagittal arachnoid cyst benefited from stereotactically guided endoscopy. We report this case because of its peculiarities and introduce technical details about the procedure which are not found in the literature.