Abstract:Tolosa-Hunt syndrome is one of painful opthalmoplegia induced by idiopathic inflammatory ganuloma in cavernous sinus or superior orbital fissure. We analysed the clinical feature, diagnosis and differential diagnosis of 22 patients with Tolosa-Hunt syndrome. The etiology of Tolosa-Hunt syndrome was discussed related with pathology. We suggested that the cause of this disease should be idiopathic inflammatory granuloma rather than vascular factor. The changes of blood vessel are secondary to inflammatory invasion.