Although it is still debated whether chronic cerebro-spinal venous insufficiency (CCSVI) plays a role in multiple sclerosis (MS) development, many patients underwent endovascular treatment (ET) of CCSVI. The objective of the study is to evaluate the outcome and safety of ET in Italian MS patients. Italian MS centers that are part of the Italian MS Study Group were all invited to participate to this retrospective study. A structured questionnaire was used to collect detailed clinical data before and after the ET. Data from 462 patients were collected in 33 centers. ET consisted of balloon dilatation (93 % of cases) or stent application. The mean follow-up duration after ET was 31 weeks. Mean EDSS remained unchanged after ET (5.2 vs. 4.9), 144 relapses occurred in 98/462 cases (21 %), mainly in RR-MS patients. Fifteen severe adverse events were recorded in 3.2 % of cases. Given the risk of severe adverse events and the lack of objective beneficial effects, our findings confirm that at present ET should not be recommended to patients with MS.