13 cases of atypical meningioma were analysed, which were proven surgically S.N.U.H. for 3 years since Marach,1979. CT findings of atypical meningioma were central low density in 8 cases, large cyst in 4 cases, calcifiedmass in 1 case and non-specific scalp mass in 1 case. All the CT findings of atypical meningioma werepathologically proven as follows. Central low density was tissue necrosis in 5 cases, multiple cyts in 2 cases andhemorrhage in a case. Large cyst was arachnoid cyst in all 4 cases. Calcified mass was massive calcium depositionon tumor. Non-specific scalp mass on temporal area was meningioma involving soft tissue, bone and dura.