Various difficulties and inconvenience arise from having a mentally handicapped child in a family and these place many demands on mothers. There are few studies in Korea on these demands nor on what mothers go through with their mentally handicapped daughters' menarche and puberty. The purpose of the study was to examine the experiences of mothers of mentally handicapped daughters, as it relates to their daughters' menarche and the beginning of puberty. With in depth interviews, both in person and by telephone and participant observation the study used a qualitative research methodology to attempt to understand the experiences of these mothers. The data were gathered from October 1995 to April 1996. The subjects for the research included nine mothers of mentally handicapped daughters whose ages ranged from 12 to 18 and who attended one of three special schools located in either Inchon or Seoul. The data were recorded and analyzed ; meaningful statements were grouped according to subjects raised by the mothers. Content Analysis was also applied to identify similar content and confirm common experiences, and to highlight concepts and categorized them. The results of this study are as follows. Five categories were identified ; mothers' emotional responses to their mentally handicapped daughters' menarche and menstruation were of severe despair accompanied by anxiety, guilt, fear, anguish, shame and pity because the mothers were afraid their daughters would not be able to use appropriate hygienic measures during menstruation and the mothers felt heavily burdened in having to look them. The mothers also had negative feelings about their daughters' physical development. The experience of mothers related to their daughters' possibilities for marriage and pregnancy were of powerlessness, distress, withdrawal, fear, pity and desperation and they were afraid that their daughters might be violated sexually. The mothers rejected the possibility of marriage and pregnancy for their daughters and instead planned very restricting futures for them. The mothers used various coping methods to bring meaning to their lives. Because the negative emotional responses of the mothers, nurses need to work to empower mothers to overcome these negative responses. Sex education can also play an important role especially for the daughters especially through the use of visual aids. Further, nurses should understand the learning difficulties of mentally handicapped daughters, what mothers need and also what they experience with their mentally handicapped daughters. In conclusion, nurses should understand the negative experiences of the mothers in relation to their mentally handicapped daughters' menarche help the mothers cope with the negative. emotions through real life education and counselling. In addition, there is a need for nursing interventions and an administrative system which will minimize the prejudices of society towards handicapped people.