Abstract: In recent years, the rapid development of urban rail transit has given rise to various environmental issues, making it an emerging hotspot in the fields of transportation and environmental research. To systematically reveal the research progress and emerging trends in this domain, this study employs CiteSpace software to conduct bibliometric and visualization analyses based on literature data retrieved from the CNKI and Web of Science databases spanning 1995 to 2025. The analysis explores multiple dimensions-including publication trends, keyword co-occurrence, clustering, and burst detection-to comprehensively examine the knowledge structure and evolutionary patterns of studies on the environmental impacts of urban rail transit. The results indicate that over the past three decades, the annual publication volume in this field has shown a steady upward trend. China and the United States have been the primary contributors, with China demonstrating a  significant lead in publication output. Current research hotspots are mainly concentrated on vibration and noise, with vibration reduction and noise mitigation remaining core research themes that continue to attract scholarly attention in recent years. Overall, future research is expected to further focus on multi-physical field coupling effects, integrated ecological impact assessment, and sustainable design strategies to promote the environmentally friendly development of urban rail transit systems.