Microplastics (MPs) in the urban atmosphere have been widely reported. However, the distribution of urban atmospheric microplastics (AMPs) under the influence of the East Asia monsoon remains unknown. In this study, total suspended particle (TSP) samples were collected, and polyethene terephthalate (PET) and polycarbonate (PC) MPs concentrations were quantified using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Higher concentrations of PET and PC were found in the dry season (176.3 ± 22.3 ng/m3 and 41.0 ± 12.6 ng/m3) compared to those in the wet season (49.6 ± 12.0 ng/m3 and 14.7 ± 6.5 ng/m3). Both the concentrations of PET and PC were negatively correlated (p < 0.05) with the frequency of southeast winds, while being positively correlated with the frequency of northwest winds (p < 0.05). Air mass trajectories of the sampling site indicate that during the wet season, a larger number of air masses originate from the oceanic direction, while more air masses come from downtown in the dry season. This further indicates the influence of atmospheric transport on the distribution of PET and PC in the air. In addition, the concentration of PET in the air was significantly correlated with the relative humidity, which may be due to the high proportion of fibrous MPs in PET.