Background: Hygienic practices during menstruation are of considerable importance, as it has a health impact in terms of increased vulnerability to infections. Menstrual hygiene management is a special problem for adolescent girls, particularly when attending school due to limited or lack of access to safe sanitary pads and good sanitary facilities. Government of India under RMNCH+A programme, introduced priority intervention for menstrual hygiene to prevent hygiene related infections. Objectives: (1) To assess the knowledge regarding menstrual hygiene among adolescent girls. (2) To assess the menstrual hygiene practices & related infections among the adolescent girls. Methods: A cross-sectional study was conducted among 330 adolescent girls who had attained menarche and residents of an urban poor locality Yarab Nagar, which comes under the field practice area of KIMS, Bangalore. Data regarding socio demographic details and menstrual hygiene practices was obtained in a pre-designed, semi structured proforma. All the subjects were examined for any related infections from a trained female doctor. The data was analysed in Microsoft Excel using mean & percentages. Results: The mean age of the study subjects was 13.63 ± 5.76 years. Majority i.e., 306 (92.7%) of them used sanitary pads; whereas, 24 (7.3%) used old clothes as an absorbent during menstruation. Similarly, 98% cleaned the external genitalia with water during menstruation. The common infections related to menstruation were contact dermatitis (7.2%), candidiasis (5.4%) & UTI (3.5%). Conclusion: The knowledge and practice regarding menstrual hygiene was inadequate among the adolescent girls; and this inadequate hygienic practices has led to infections.