Due to their large specific surface area and strong hydrophobicity, microplastics (MPs) are highly susceptible to adsorb environmental pollutants, of which heavy metals (HMs) are the most representative inorganic pollutants. However, there is controversy in different studies as to whether the toxic effects of the combined action of MPs and HMs on zebrafish larvae are antagonistic or synergistic. Herein, we firstly evaluated the combined effects of 10 μm polystyrene MPs (PS-MPs) on zebrafish larvae after exposure for 96 h at two different concentrations (5 mg/L, 0.5 mg/L) and Cu