Marine biological pollution is a worldwide problem that poses a significant challenge in marine engineering. MXene nanosheets and zwitterionic polymers are promising materials for marine anti-biofouling and have attracted much attention. Herein, we self-assembled the polydopamine layer on the surface of MXene nanosheets (MXene-PDA), and then introduced the zwitterionic polymer (PEIS) by Michael addition reaction onto the PDA layer to obtain the zwitterionic polymer-functionalized MXene nanosheets (MXene-PEIS). The as-prepared MXene-PEIS exhibits excellent antifouling performance through the cooperative antifouling effect between the MXene nanosheets and the zwitterionic polymer PEIS (the antibacterial rate improved by 88 % and there was a 98 % decrease in microalgae adhesion density). Moreover, the nanocomposite antifouling coatings (MXene-PEIS/SP) were obtained by blending the as-prepared MXene-PEIS nanosheets with self-polishing coatings. The results show that MXene-PEIS/SP coatings have good antifouling performance due to the synergy between MXene, PEIS, and self-polishing coatings.