Objective To investigate the clinical application and surgical techniques of lateral-orbital keyhole approach to clip ruptured tiny aneurysms.Methods A retrospective analysis was performed on the clinical data of 56 patients with ruptured tiny aneurysms, including examination methods, imaging features, diagnosis and treatment process, and operation effect, which underwent lateral-orbital keyhole approach from January 2013 to April 2014.Results Among 56 patients with a total of 61 aneurysms(56 tiny aneurysms) was examined by CT angiography (CTA) and/or digital stubtraction angiography (DSA), all achieved successful clipping with a rupture rate of 16％(13 cases).Forty-two cases got a good recovery,8 cases owned the self-care ability, and 6 cases could carry out daily lives with help.There was no rebleeding and mortality, according to a 2-28 months' follow-up of 49 patients.Conclusion As a surgical approach for Willi'S cycle aneurysm,the lateralorbital approach is simple,rapid,minimally-invasive way.It is available in the clipping of ruptured tiny anterior communicating aneurysms.The option of operative time, perfect microdissection and exquisite intraoperative microinvasive operative skills, will be the key point of clipping aneurysms, preventing and controlling of intraoperative bleeding.