An antibacterial composite is disclosed, where an antibacterial material is encapsulated by a microemulsion to form the microemulsion having the antibacterial material for inhibiting harmful bacteria, and the microemulsion having the antibacterial material is combined with a dendrimer. Due to the hydrophilic/hydrophobic differences between the antibacterial composite and the plastic substrate, the antibacterial composite is retained on the surface of the plastic substrate so as to increase the surface concentration of the antibacterial composite on the plastic substrate to improve the antibacterial effect. The present invention also relates to a method for manufacturing the antibacterial composite.