Menarche or the first menstruation is the final stage of puberty in female children. The age at menarche is lowering globally. Individuals with earlier menarche are more likely to get cancer due to hormonal abnormalities. It is important to understand the risk factors of early menarche. Factors, such as nutritional status and vitamin D, may affect the onset of menarche. This research was an analytical cross-sectional study conducted to assess the relationship of nutritional status and vitamin D levels with age at menarche of girls at Darul Ihsan Islamic boarding school in Hamparan Perak, North Sumatra, Indonesia. Research subjects were female children between eleven and fifteen years old who had reached menarche. Body weight and body height were measured to obtain nutritional status data. Tanner stage examination was carried out to each of the research subject. Blood sample was drawn for serum 25(OH)D examination. Bivariate analysis was carried out to determine the following relationships, vitamin D level and menarche age, nutritional status and vitamin D level, and nutritional status and menarche age, with P value < 0.05 considered significant. The mean menarche age was 11.79 years old, where thelarche occurred at a mean age of 10.5 years old. Almost all of the research subjects (38/95%) had vitamin D deficiency, while two (5%) subjects had vitamin D insufficiency. There was no significant relationship (p > 0.05) between vitamin D level and age at menarche. Nutritional status and vitamin D were not significantly related. However, there was a significant relationship between vitamin D level and age at thelarche (p = 0.017).