We reported on syringomyelia in a mother and her son. The mother was 74-year-old, who developed gait difficulty at the age of 54. The son, 47-year-old, developed the same symptoms at the age of 35. In the both cases, MRI revealed syringomyelia with Chiari malformation. Twenty-one families with syringomyelia have been reported. The existence of these families indicates that genetic factors may play in role to the pathogenesis of this disorder.