Medical devices-related infections pose a great threat to patients and cause an increased morbidity and mortality.Herein,we prepare an antibacterial composite(TPU-x)through blending medical grade thermoplastic polyurethane(TPU)and the complex(PL-DOSS)of e-polylysine(ε-PL)and docusate sodium(DOSS).>99%reduction of colony forming unit(CFU)can be obtained in TPU-x composite films even at relatively low content of PL-DOSS,e.g.0.13%for Methicillin resistant S.aureus(MRSA)and 0.5%for E.coli.The excellent antibacterial activity is mainly attributed to the formation of PL-DOSS nanoparticles that are uniformly dispersed in the TPU matrix with a size of~100 nm.TPU-x composite films exhibit long-term stability in saline and good biocompatibility,and retain mechanical properties of TPU.