This study was designed in an attempt to identify the risk factors that could be significantly associated with angiographic recurrences after selective endovascular treatment of aneurysms with inert platinum coils. A retrospective analysis of all patients with selective endovascular coil occlusion of intracranial aneurysms was prospectively collected from 1999 to 2003. There were 455 aneurysms treated with inert platinum coils and followed by digital subtraction angiography. Angiographic results were classified according Roy and Raymond's classification. Recurrences were subjectively divided into minor and major. The most significant predictors for angiographic recurrences were determined by ANOVAs logistic regression, Cochran-Mantel-Haenszel test, Fisher exact probability. Short-term (4.3 ± 1.4 months) follow-up angiograms were available in 377 aneurysms, middle-term (14.1 ± 4.0 months) in 327 and long-term (37.4 ± 11.5 months) in 180. Recurrences were found in 26.8% of treated aneurysms with a mean of 21 ± 15.7 months of follow-up. Major recurrences needing retreatment were present in 8.8% during a mean period follow-up of 17.9 ± 12.29 months after the initial endovascular treatment. One patient (0.2%) experienced a bleed during the follow-up period. Recurrences after endovascular treatment of aneurysms with inert platinum coils are frequent, but hemorrhages are unusual. Single aneurysm, ruptured aneurysm, neck greater than 4 mm and time of follow-up were risk factors for recurrence after endovascular treatment. The retreatment of recurrent aneurysm decreases the risk of major recurrences 9.8 times. Long-term angiogram monitoring is necessary for the population with significant recurrence predictors.