BackgroundAdolescent girls, particularly in lower socioeconomic settings, lack adequate knowledge of menstrual hygiene management and have subpar hygiene habits. Likewise, the factors related to it have not been well addressed, and schoolgirls are facing a range of challenges. To develop effective intervention approaches, a context-specific assessment of menstrual hygiene practices is useful. Thus, this study aimed to assess menstrual hygiene management knowledge, practice, and associated factors among girls in the Boset district, Ethiopia.MethodsA school-based cross-sectional study was conducted at Boset district secondary schools among 629 randomly selected girls using the multi-stage sampling technique. Data were collected using a self-administered, structured questionnaire. The collected data were entered into Epi-info version 7 and analyzed by Statistical Package for Social Science (SPSS) version 26. Binary logistic regression analysis was used to model the association between dependent and independent variables. An adjusted odds ratio and 95% confidence interval were used to measure the strength of the association, and a p-value < 0.05 was used to declare statistical significance.ResultOf the total study participants, 51.2% (95% CI: 46.6–55.8%) had an appropriate practice of menstrual hygiene and 57.9% (95% CI: 53.3–62.5%) had good knowledge status on menstrual hygiene management. Being an urban resident (AOR = 1.84, 95% CI: 1.20–2.80), having a mother with a secondary and above educational level (AOR = 3.4, 95% CI: 2.07–5.57), earning regular pocket money (AOR = 2.19, 95% CI: 1.45–3.313), and discussing menstrual issues with parents and friends (AOR = 3.65, 95% CI: 2.327–5.727) were associated with good practice of menstrual hygiene.ConclusionIn this study, nearly half of the school girls had good practice and knowledge of menstrual hygiene management. Educating mothers and promoting discussion about menstrual hygiene management issues, especially in rural areas, should be priority actions.