This study focuses on the age get menstruation first time (menarche), the length of menstruation period, and the source the santri's knowledge about menstruation. The subject of the study is female santri of PP Mabdaul Ma'arif PP As Sunniyah Kencong Jember. The study is a ase study. The data is collected through documents, questionnaires, and interview. The data analysis is a descriptive anal…