Menstrual hygiene management (MHM) is an essential aspect of hygiene for women and adolescent girls between menarche and menopause. The menstruation cycle is treated as something dirty, impure, and contaminated. Girls and women are alienated from society as well as their friends and families during this time of the month. They are forced into harmful social restrictions and have to face the human condition and humiliation. The objective of the study was to measure the knowledge and self-care practices of adolescents on menstrual hygiene. A mixed method of qualitative and quantitative study designed to access the knowledge attitude and self-care practices, social cultural practices food taboos during menstrual hygiene among 459 adolescent girls of urban area in the Government Schools of Kathmandu Valley from 23, August 2019 to May 29, 2020. Semi-structured open-ended questionnaires along with a Likert scale and in-depth interviews were done among selected 92 students based on scoring of the Likert scale, focusing on socio-cultural practices, food beliefs and practices, and feelings and emotions during menstruation. The interview was accompanied by concurrent note-taking in the Nepali language which was later translated to English. The code book was generated and thematic data analysis was conducted. The result showed that 19.72% of students need improvement in attitude towards menstruation. Menstruation is taken as a secretive and indiscriminate management practice. During menstruation, 83.09 % of students used old and used cloths as absorbent, and 46.5 % disposed of their used pads by throwing them with other waste. Change of pad depending upon their bleeding was practiced by 54.9% of the student. More than half of the students i.e. 60.6% students don’t take a bath every day during their periods. Even though all adolescents have facilities of the toilet but they are still facing the problem of water which, is a great obstacle for them to maintain their menstrual hygiene. Sociocultural rituals of the menstrual cycle are hampering the self-esteem of the girl's student, for which there is a needto focus on interventional study and MHM programs that suitably address the problems of adolescent girls.