Background <p>Menstrual hygiene management is a critical aspect of adolescent girls' health, yet knowledge gaps remain in many developing countries, including Indonesia. With the increasing use of digital media among adolescents, this study aims to evaluate the effectiveness of digital electronic media in improving menstrual hygiene knowledge among adolescent girls in junior high schools in Bandung Regency.</p> Methods <p>A quasi-experimental design was used involving 180 adolescent girls from six junior was used. The intervention group received validated educational content on menstrual hygiene through digital electronic media, including an animated video and an interactive booklet. The control group followed traditional educational methods. Knowledge was assessed using a 25-item validated questionnaire (Cronbach’s alpha = 0.81) through a pre-test and post-test format. Statistical analysis included Difference-in-Differences (DiD), paired and independent t-tests, and Mann–Whitney U tests.</p> Findings <p>There was a significant improvement in menstrual hygiene knowledge in the intervention group compared to the control group (mean DiD effect: 12.5 points; 95% CI: 10.2–14.7; <i>p</i> &lt; 0.001). Public school students exhibited more pronounced improvements. Key areas of knowledge gain were hygiene practices and myth correction.</p> Interpretation <p>Digital media effectively enhances adolescent girls' menstrual hygiene knowledge and attitudes. This approach is scalable and cost-efficient, particularly for low-resource settings.</p> Funding <p>Institut Kesehatan Immanuel.</p>