Objective ‒ to analyze the effectiveness of intraoperative contact Doppler, repositioning the clip on the aneurysm and pilot clipping of the cervical aneurysm as the main methods of prevention of inadequate clipping of the cervical aneurysm in patients with intraoperative rupture of aneurysms. Materials and methods. Due to the use of intraoperative contact ultrasound Doppler control it was possible to avoid inadequate clipping of cerebral aneurysms in 16 cases, of which in 12 (75.00 %) cases ‒ incomplete clipping of cerebral aneurysms, in 3 (18.75 %) cases ‒ compression of the aneurysm’s artery-carrier, in 1 (6.25 %) case ‒ slipping of the clip with cerebral aneurysm. Perioperative examination of patients, in addition to intraoperative contact ultrasound Doppler control of radical clipping cerebral aneurysms, included clinical and neurological examination, computed tomography of the brain, cerebral angiography, ultrasound duplex scanning of the main vessels of the head and neck. In the analysis of observations of inadequate clipping of cerebral aneurysms (according to contact intraoperative Doppler), the following parameters were considered: size, location of cerebral aneurysm, timing of surgery after subarachnoid hemorrhage, anatomical forms of intracranial hemorrhage. Results. The purpose of the operations was to devascularize saccular aneurysm to prevent its re-rupture, to reduce the mass effect caused by intracerebral hematoma; reduction of intracranial pressure, rehabilitation of basal cisterns of the brain., But in the postoperative period there was a tendency to worsen the results of treatment, the appearance of focal neurological symptoms on the background of cerebral vasospasm with subsequent development of ischemic complications in patients with III‒V degree according to the Hunt‒Hess Scale on admission, in patients with prolonged temporary clipping of the cerebral aneurysm-artery and prolonged mechanical manipulation of the cerebral arteries and cerebral aneurysm. It should be noted that all patients in our sample, with complicated clipping of cerebral saccular aneurysms, had an intraoperative rupture of the MA, which complicated the process of clipping the saccular aneurysm and prolonged the time of surgery and was one of the inducers of postoperative aggravating consequences. There was a tendency to worsen the results of treatment in patients with III–IV degree according to the Hunt‒Hess Scale. Thus, patients with 1 point according to the Glasgow Outcome Scale, there were 2 patients who had II and III degrees according to Hunt–Hess Scale at hospitalization; among discharged patients with 3 point according to Glasgow Outcome Scale was dominated by patients from the second century according to Hunt‒Hess Scale at hospitalization, among patients with 5 point according to Glasgow Outcome Scale dominated patients who had I degree according to the Hunt‒Hess Scale at hospitalization. Conclusions. Inadequate clipping of the cervix cerebral aneurysm is the main type of non-hemorrhagic complications in the surgery of cerebral aneurysms. The Inadequate clipping of the cervix of the cerebral aneurysm includes the presence of residual blood flow in the cerebral aneurysm after its clipping, stenosis/compression of the main and perforating cerebral arteries with a clip, slipping of the clip from the aneurysm. Among the factors influencing the radical and adequate clipping of the cervix cerebral aneurysm are the size, location of the aneurysm, atherosclerotic lesions of the walls of the arteries and neck of the aneurysm and transferred subarachnoid hemorrhage. Reliable methods of prevention of inadequate clipping of saccular aneurysm are the use of intraoperative Doppler blood flow control, pilot clipping of complex aneurysms, optimization and individualization of surgical access. Aggravating factors that lead to unsatisfactory results of treatment of patients and negative clinical dynamics after the operation of clipping cerebral saccular aneurysm are: severe condition of the patient before surgery (III‒V gr. according to the Hunt‒Hess Scale), severe cerebral edema, intraoperative rupture of saccular aneurysm, long-term mechanical manipulations on cerebral arteries (long-term temporary clipping of saccular aneurysm, isolation of saccular aneurysm and «neighboring» cerebral arteries from arachnoid adhesions, frequent repositioning of the clip).