An occlusion device for vascular surgery, suitable for clogging treatments of vascular entry sites and for endovascular interventions such as embolizations of blood vessels, treatment of arteriovenous malformations or small aneurysms, arterial dissections and the like, by releasing in an operation region a quick setting surgical glue or haemostatic fluid, through an outlet mouth of a duct. The device prevents the surgical glue from contacting within the duct a patient's biological fluids, in particular blood, which would close the duct. In the case of clogging treatments of vascular entry sites, a backflow preventing device may be provided, preferably provided by a coupling device between the duct and an introducer sheath by which an outlet mouth is kept in contact to keep in a one-way fluid tight contact against the outer surface of the introducer sheath until an injection pressure P2 is applied to cause release of the surgical glue.
