Ultrasound has the advantages of being environmentally friendly and enhancing the collision and aggregation of suspended particles, while the potential for microplastics (MPs) treatment in aqueous environments is yet to be explored.This study investigated the role of ultrasound in promoting the aggregation of MPs in aqueous environments to achieve their removal, and found that ultrasonic power, temperature, and time are key factors influencing MPs aggregation.Optimization achieved maximum aggregation rates of 64.8 % for PVC and 53.5 % for PE, and the optimal conditions for aggregation were ultrasound power of 230 W, 22 °C, ultrasound for 7 min, and ultrasound power of 153 W, 22 °C, ultrasound for 4 min, resp.Fourier transform IR spectroscopy and at. force microscopy analyses of the properties of MPs before and after aggregation revealed that ultrasonic input reduced the surface roughness of MPs from 676.6 nm to 499.7 and 107.1 nm, resp., accompanied by a reduction in elec. potential by 3.3-4.4 V, which was identified as the primary cause of aggregation.Theor. calculations indicated that the binding energies of PVC and PE were -12.82 and -7.75 kJ·mol-1, resp., further confirming that electrostatic force play a dominant role in MPs interactions.Moreover, the differences in aggregation effects depended on variations in the physicochem. properties of different types of MPs.COMSOL simulations further validated the possible process of MPs aggregation induced by ultrasound in aqueous environments.This study offers new insights into the removal of MPs in aqueous environments and is expected to develop a green and efficient treatment technol.