To diagnosis Tolosa-Hunt syndrome (TSH) used to be difficult because some other diseases like tumors, sarcoids, vasculitises or other inflammatory masses simulate the clinical manifestations, including steroid responsiveness and radiologic findings. According to the international classification of headache disorders 2nd edition, the diagnosis of THS requires demonstration of granuloma by MRI or biopsy. We performed MRI 4 times during 6 months in a patient who seemed to have THS. Initial MRI was normal but the second MRI showed granuloma which decreased gradually in size with steroid treatment. Key Words : Tolosa-Hunt syndrome, Magnetic resonance imaging, Granuloma