Abstract In this study, the quantitative and qualitative compositions of microplastics (MPs) deposited from the atmosphere in the coastal zone were analysed. Moreover, links between MP deposition and meteorological factors (air humidity, wind speed, precipitation height, and air mass trajectories) were investigated. MP deposition samples were collected in the southern Baltic area in 2017 and 2018 for 286 days in total. The morphological features of MPs (shape and size) were analysed using a digital microscope. Qualitative analysis was performed using micro-attenuated total reflectance Fourier-transform infrared spectroscopy (μATR FT-IR). The size of the deposited MPs ranged from 5 μm to 5000 μm, and smaller size classes (