We evaluated the clinical and angiographic results of endosaccular treatment with Guglielmi detachable coils (GDCs) in 19 cases of cavernous internal carotid artery (ICA) aneurysms. The size of the aneurysms ranged from 10 to 30 mm (mean 18.4 mm) and neck size ranged from 2 to 15 mm (mean 6.7 mm). Intraluminal thrombosis was found in ten cases. Main presenting symptoms were related to mass effect in 17 cases including cranial nerve palsy, headache and vomiting. On initial GDC embolisation, total occlusion was obtained in two cases, subtotal in eight, and incomplete in nine. In two cases with incomplete occlusion, parent arteries were occluded with balloons or GDCs during or just after the procedure because of underlying diseases. A higher rate of initial occlusion was obtained in smaller and non-thrombosed aneurysms. Symptoms resolved or improved in all cases except one after initial treatment. No complication occurred related to the procedure. Follow-up angiography was obtained in 15 cases among which ten cases (66.7%) showed luminal recanalisation. Symptoms recurred in one case with luminal recanalisation. Incidence of recanalisation was similar in both large and giant aneurysms but higher in the thrombosed than non-thrombosed group. Retreatment was done in five cases with success. In conclusion, although embolisation of cavernous ICA aneurysms with GDCs was safe and effective in relieving symptoms, the incidences of initial incomplete occlusion and follow-up recanalisation were high. Therefore, we think judicious selection of the cases is necessary for endosaccular GDC embolisation in cavernous ICA aneurysms.