Abstract： Objective To present our experience with retrograde suction decompression in clipping of large and giant internal carotid artery aneurysms and analyze its advantages and pitfalls.Methods A retrospective analysis of 26 large and giant intracranial aneurysms treated by suction decompression assisted clipping between November 2005 and February 2010 was present.The surgical techniques and the outcome of patients were reviewed.Results All aneurysms were successfully clipped, and postoperative 3D - CTA or DSA revealed no major branch occlusion or residual aneurysm.There was no surgical mortality in both giant and large aneurysm groups.Conclusions Retrograde suction decompression is a successful adjunct to clipping of large and giant internal carotid artery aneurysms.