Spontaneous regression of meningioma is rarely observed. We report a one person of an incidentally diagnosed meningioma with a spontaneous regression. The 73-year-old female patient without symp- toms showed the right sphenoid meningioma with peritumoral edema. The meningioma was inciden- tally diagnosed and followed up by MRI for 10 years. The tumor shrank with a decrease of edema on T2 MRI. The initial volume of 58.59 cm3, regressed to 37.16 cm3.