Menstrual hygiene management (MHM) is an important but often neglected aspect of women’s health worldwide, especially in developing and disaster-prone countries, such as Bangladesh. This qualitative study aimed to investigate awareness, attitudes, and practices related to MHM among girls in the Haor region, particularly during floods. The study adopts a phenomenological approach, and data were collected using purposive sampling from 33 women aged 15 years and above who resided in the Haor region. Thematic analysis was employed to identify the patterns, themes, and subthemes within the qualitative data. The study reveals a significant lack of widespread knowledge about menstruation among girls in the Haor area, which is associated with unfavourable family and social attitudes, and stigma or taboos. Natural hazards, cultural barriers, access to the market, economic incapacity, and inadequate infrastructure make it very difficult to manage menstruation, which is especially aggravated during floods due to displacement and shelter on the roadside, primary schools, and other people’s houses. This research emphasises the need for tailored MHM programmes from the government to address the unique challenges faced by women in Haor regions. Provision of sanitary napkins and essential medicines, maintaining stock in shelters, and equipping community clinics with MHM-related healthcare services are essential. Finally, NGOs should prioritise MH within their scope of work.