Objective. The study objective was to evaluate the efficacy of occlusions of large and giant intracranial aneurysms with microcoils using stent assistance (SA). Material and methods. The study is based on analysis of treatment outcomes in 37 patients with large (15—25mm) and giant (more than 25mm) intracranial aneurysms, aged 18 to 72 years, who were hospitalized at the Burdenko Neurosurgical Institute in the period between 2004 and 2014. Selection of patients for endovascular treatment using SA was based on the anatomical parameters of the aneurysm and carrier vessel. The main determining factor was the index of the aneurysm body to neck size ratio. Occlusion of aneurysms was performed with microcoils of different configurations, including those with a biologically active coating. Self-expanding stents with both an open-cell and closed-cell design were used for SA. The results of intervention for large and giant aneurysms were evaluated using control angiography immediately after occlusion of the aneurysm. The condition of patients with unruptured aneurysms as well as with ruptured aneurysms in the “cold” period was evaluated using the modified Rankin scale. The condition of patients in the acute period of SAH was evaluated on the Hunt and Hess scale. Results. The technical success (successful implantation of stents and coils with total or subtotal aneurysm occlusion) was 94.5%. The postoperative disability was 2.7%; mortality was 2.7%. 28 patients were followed up for the period of 5 to 84 months (the mean was 20 months.). In the long-term period, the total and subtotal occlusion rate, including the results of re-operations, amounted to 90%. Delayed disability was 10.7%, and mortality was 3.5%. Conclusion. Stent assistance enables achieving total or subtotal occlusion of large and giant aneurysms in 90% of cases. In certain clinical situations, it is an alternative to other existing methods.