The exact mechanism of idiopathic intracranial hypertension (IIH) is unknown. It needs to be treated because of severe headache and impaired vision. For medically refractory patients, cerebrospinal fluid diversion, optic nerve sheath fenestration and dural venous sinus stenting is applied to relieve the symptoms. As a new therapy, the complication of dural venous stenting was a focus for operators. Here, a woman is reported with IIH who suffered from mastoiditis after stenting in the sigmoid sinus for the first time. The special local anatomy of the sigmoid sinus adjacent to the inner structure made it a noteworthy complication.