The acceleration of industrialization and urbanization has led to prominent air pollution issues, with particulate pollutants in urban street canyons posing significant threats to human health and environmental safety. This paper, based on the CiteSpace knowledge mapping tool, utilizes the China National Knowledge Infrastructure (CNKI) and Web of Science as sources for Chinese and English literature, respectively. By reviewing relevant literature from 2004 to 2025, it identifies and extracts 118 Chinese core articles and 137 English core articles. The study conducts a visual analysis of the research on particulate pollutants in urban street canyons from perspectives such as publication trends, leading authors, research institutions, research hotspots, and future directions. The findings indicate that the volume of publications on particulate pollutants in urban street canyons has generally shown an upward trend, with a notable increase particularly after 2010. Scholars both domestically and internationally have formed several relatively independent collaborative groups in this field. The research directions are categorized into four major areas: the impact mechanisms of street greening on pollutant dispersion, simulation studies of air flow and pollutant dispersion, the influence mechanisms of street canyon spatial morphology on pollutant dispersion, and the correlation between traffic pollution and street canyon structure on pollutant dispersion.