Ger districts in Ulaanbaatar accommodate approximately 30% of the city’s population and are steadily expanding into the city’s outskirts. They are primarily inhabited by former nomadic households undergoing a rapid urban transition. This transformation has led to spatial and social challenges, particularly a deficiency in public open spaces. Access to multifunctional recreational spaces is of paramount importance for fostering community interaction, improving public health, and enhancing the overall quality of urban life. However, the scarcity of recreational and green spaces in ger districts constrains everyday life and weakens the social infrastructure necessary for community well-being. Based on theories of public space and sustainable urban development, this study examines the demand for public open spaces in ger districts through questionnaire surveys and field observation. The study evaluates residents’ spatial needs, usage patterns, and perceptions of environmental quality. The findings reveal that a critical shortage of recreational areas, playgrounds, sidewalks, and accessible green spaces, limiting opportunities for social cohesion and restorative experiences. In addition, residents tend to utilize water kiosks and local grocery stores as gathering places and landmarks. The study argues that the strategic integration of inclusive, multifunctional public open spaces should be considered a priority in the sustainable redevelopment of ger districts. Such spatial interventions are essential not only to improve environmental performance but also to strengthen social resilience and enhance long-term urban livability.