At Burdenko Neurosurgical Institute annually arrives 50-60 patients with large and giant aneurysms of the brain, which is nearly 15% of all patients with aneurysms. About half of them - patients with paraclinoid aneurysms, which are successfully treated by cliping using techniques of intravascular blood aspiration (IVBA) or proximal control of blood flow in the neck. This paper analyzes the long-term outcomes of patients who were operated for large and giant aneurysms of the internal carotid artery in the last 15 years. Catamnesis was collected from 93 (71.5%) of 130 patient. Mean follow-up was 65.2±36.0 months. Mean age of patients at the time of surgery was 45.55±7.5 years and at the time of catamnesis evaluation - 50.4±10.2 years. Men to women ratio was 18:75. Patients with multiple aneurysms was 22.6% (21 patients). In most cases - 67 (72%) patients - aneurysms were treated by cliping of aneurysms using IVBA, in 14 (15%) cases - using proximal control of blood flow in the neck, in 5 (5.4%) cases - reinforced with gauze and glue, in 6 (6.5%) patient - by aneurysm trapping, in one case the aneurysm was not cliped. Radical surgery performed in 87 (93.5%) patients. Catamnesis analysis of survived patients showed that 55.8% of them are complaining of headaches, which they associate with the operation. 39 (43.3%) patients noted persistent elements of asthenia, 4 (4.6%) had sleep disorders, 5 (5.8%) suffered of epileptic seizures and 1 (1.1%) - of depression. Korsakoff's syndrome, developed after surgery in 2 (2.3%) patients remains. Only 38.4% of patients after surgery continue to work. Favorable outcome on the Glasgow outcome scale (4-5) was obtained in 81 (87.1%) patients, poor (2-3) in 5 (5.4%) patients. Mortality rate was 7.5%. Severe oculomotor disturbances have a slight tendency to recovery over time.