Abstract: Cutis.hyperelastica.occurred in a 18-year-old girl.She had bed-wetting from childhood,primary amenorrliea and lack of axillary and pubic hairs,Examination of chromosome of the patient aid her parents showed no abnormality in quantity or morphology.Under electrorimicroscope,the ultrastructure of patient's platelet was normal,but striations of the collagen fibres with a periodicity were sliortened about 300-3801,(640-7001 in normal).This paper emphasized the importance of the investigation of genetic skin disorders in the planned parenthood and eugenies.