Background: Idiopathic intracranial hypertension (IIH) is a disorder characterized by increased intracranial pressure (ICP) of unknown cause, predominantly seen in women of childbearing age and associated with a history of recent weight gain. There is little published evidence comparing lumbar puncture with medication or other treatment modalities. Objective: to study the effect of introduction of therapeutic lumbar puncture on the visual outcome and the further need for surgery in patients with IIH (grade II papilloedema) Patient and methods: This prospective study included all the patients with IIH diagnosed according to the modified Dandy criteria with grade II papilloedema, managed at the Neurosurgical Department – Benha University between January 2009 and January 2014.The patients were randomly assigned into two groups A and B according to the inclusion of therapeutic lumbar puncture. Results: The mean time at which headache decreased to nearly half the initial was 8.1 days (group A) and 4.7 days (group B).Five patients in group A and three patients in group B progressed to grade III papilloedema and lumbo-peritoneal CSF diversion was planned. In the first monthly-visit, 12 patients in group A and 13 patients in group B showed gradual improvement to grade I while 5 patients in group A and 6 patients in group B showed gradual improvement to grade 0 and at the end of follow up period all these patients reached grade 0 papilloedema . The rate of success of treatment was 77.2% in group A and 86.3% in group B. Conclusion: The results of this study favor the introduction of therapeutic lumbar CSF puncture together with the other non-surgical maneuvers in the management of IIH with grade II papilloedema.