Aim To discuss the cause and methods and complications of endovascular therapy of carotid-cavernous fistulas. Methods Were analyzed clinical expression and imaging characteristic of CT, MR, and selectivity angiogram in 19 cases of carotid-cavernous fistulas. They were treated by detachable balloon and/or coil emoblization. Results Clinical symptom relieved in 17 cases, optic cacophony and nystagmus disappeared, exophthalmos and the dropsy of conjunctiva disappeared after a week of emoblization therapy. 2 patients showed surgical complications, of which a patient has been dead. Conclusion The methods of endovascular therapy was safe and reliable, which has been chiefly wsed to treat carotid-cavernous fistulas.