Objective To explore classification methods and Surgical techniques of the squama occipitalis deformities.Methods A retrospective analysis from 2001 to 2008 treated 16 cases of squama occipitalis deformties,according to MR findings,put forward classification method of the squama occipitalis and diagnostic criteria of foramen magnum trailing edge and the occipital scale department hypertrophy.Results All patients after the use of median incision posterior fossa decompression,the clinical symptoms in patients with varying degrees to resume.Conclusion It is important to the squama occipitalis deformities on reasonable classification has obvious clinical instruction value on preoperative assessment and the operation.