Background: The superficial temporal artery (STA) to proximal middle cerebral artery bypass has been reported before. However, the flow supply capacity of the double-barrel STA to proximal MCA bypass in treating complex intracranial aneurysms has not been well documented. Methods: Consecutive cases using double-barrel STA to proximal MCA bypass to treat complex intracranial aneurysms during the past 5 years were collected. Somatosensory evoked potential monitoring and motor evoked potential monitoring were applied for each patient to identify any ischemic events during surgery. After bypass, the aneurysm was trapped, or the proximal parent artery was occluded. Digital subtraction angiography or computed tomography angiography was used to evaluate the patency of bypass postoperatively. Blood flow was measured by ultrasound before discharge. Results: Among 1561 patients treated for intracranial aneurysms in our institute, 6 were included for the current report. There were 2 dominant M2 fusiform aneurysms, 2 M1 fusiform aneurysms, 1 supraclinoid internal carotid artery fusiform aneurysm, and 1 M1 bifurcation giant aneurysm. All 6 cases were successfully treated using this technique. One patient had temporary numbness in the contralateral extremities, which was caused by perforator complications. The blood flow carried by the STA was 108–232 mL/minute. Conclusions: When anastomosed to proximal branches, a double-barrel STA to MCA bypass can reliably provide a high blood flow of >100 mL/minute. Combined with aneurysm trapping or parent artery occlusion, this bypass algorithm could be an alternative treatment for complex intracranial aneurysms. ? 2019 Elsevier Inc.