Objective: The purpose of our study was to evaluate the results of endoscopic third ventriculostomy (ETV) in the management of patients with idiopathic normal pressure hydrocephalus (INPH). Methods: Our prospective study included seven patients (five men and two women; ages ranging between 68 and 78 years) with two or more typical NPH symptoms of short duration (<6 months), with no other morbidity factors, with a Mini-Mental State Examination (MMSE) score ≥18, aqueductal cerebrospinal fluid (CSF) stroke volume ≥42 μL, and positive lumbar drain test. The etiology of NPH was idiopathic in all of these cases. Their preoperative work-up included brain magnetic resonance imaging (MRI) and cine-MR, MMSE test, and CSF lumbar drain test, in all cases. The clinical status of all participants was graded using the Japanese intractable hydrocephalus system. An ETV was performed in all participants. Follow-up included periodic clinical evaluations, MMSE, and MRI with cine-MR studies. The follow-up time range was 12-72 months. Results: The mean postoperative clinical grade was 3.1, while the preoperative was 6.1. Gait disturbance and urinary incontinence were the most responsive symptoms. The mean postoperative MMSE score was 23.6, while the preoperative score was 20.3. The mean postoperative aqueductal CSF stroke volume, 6 months after the procedure, was 31.6 μL, while the preoperative volume was 48.8 μL. Conclusions: ETV may be a safe alternative surgical option for a limited number of carefully selected INPH patients.