Introduction: Yemen is among the most water-stressed countries in the world, due to a naturally dry climate, regional drought in recent years, and falling groundwater levels due to unsustainable drilling. This work aimed to assess the current knowledge and practices on water, hygiene, and sanitation in conflict-affected communities and internally displaced people in selected districts of Abyan governorate - Yemen. Methods: A community-based cross-sectional house-to-house survey was conducted in 2019 in three rural districts in Abyan governorate, Yemen. A total of 446 households were randomly selected and a structured interview questionnaire was used to collect data from the respondents through face-to-face interviews. Data were checked, cleaned, and entered to the SPSS version 22 for analysis. Results: The participants had inadequate knowledge and practices on water, sanitation, and hygiene. Only less than a quarter of the participants received any related education. The surveyed households had poor socioeconomic conditions such as poverty and illiteracy. Both water quantity and quality were inadequate, open defecation still exists, and open dumping of solid waste is common. Conclusion: This study calls for an urgent solution to address the challenges regarding inadequate quantity and quality of water in the surveyed areas. Moreover, it is of paramount importance to address the socio-economic vulnerabilities such as poverty, and illiteracy, and to maintain medium- and long-term solutions for water provision and environmental sanitation. For effective implementation of these solutions, education tailored to the context and the need of the population should be designed.