The issues involving menstruation are the topic of many scientific inquiries in the fields of medicine, psychology, sociology and anthropology. The aim of this study was to determine the age at menarche and the most common symptoms of premenstrual syndrome (PMS) in adolescent girls with intellectual disability. The main method of data collection was through the use of a survey and an interview with the girls. The sample consisted of 31 adolescent girls with intellectual disability and 31 adolescent girls without intellectual disability serving as a control group. Both groups were between the ages of 14 and 18 years. The results of this study revealed higher variability of age at menarche in girls with intellectual disability compared to girls without intellectual disability. The symptoms of PMS were almost equally distributed in both groups of girls. Many girls with intellectual disability do not have enough knowledge about menstruation. More attention needs to be given to treating the symptoms of PMS and educating the girls in a school setting.