The Southeast Asian region is at the center of many issues associated with the use and disposal of plastics worldwide, with growing concern over the impacts of plastics on the ecosystem and human health. The emerging topic of atmospheric microplastics transport is a potentially important pathway linking urbanized areas and waste disposal sites to coastal and marine habitats. The project aims to develop an understanding of the variety, traits, origins, and movement of microplastics in various coastal environments in Southeast Asia. In order to understand how coastal environments affect atmospheric microplastics, or vice versa, the connection between microplastics in air and surface seawater samples will be examined. The proposed study is anticipated to generate cross-country comparisons of the type, level, and source of microplastics in air and surface seawater samples. To enable harmonization and intercomparison of data on microplastic concentrations and characteristics across nations, a uniform approach for microplastic analysis in air and surface seawater samples would be developed. The pilot network created as a result of this project is anticipated to increase the scientists’ capacities and show results at the community and policy levels.