Polymers have been widely used in different areas due to their ability to cover a broad spectrum of properties. Polyethylene (PE) with antimicrobial properties is widely used in many industries, e.g. food packaging industries, medical instruments, and building water tanks. In polyethylene, microbial contaminations are of main concern. The application of antimicrobial agents into the polymer products is one of the methods to prevent the products from microbial contaminations. Nowadays, approaches that can endow polymers with anti-infective properties mainly contain (a) mixing antibacterial reagents in bulk polymers; (b) copolymerization of antibacterial reagents with monomer for polymers; (c) surface modification of polymers. In this study, triclosan (2,4,4-trichloro-2-hydroxydiphenyl ether) was used for preparation of antibacterial polyethylene compound. Triclosan is a synthetic, nonionic, and broad spectrum antimicrobial agent. Triclosan is an odorless, tasteless and non-toxic antibacterial agent displaying high chemical stability and persistent activity. Its efficacy and safety in use have led to its wide use in such products as soaps, deodorants, toothpastes, detergents, lotions, acne creams with a typical concentration in the range of 0.1-0.3% and plastics. Triclosan acts by blocking the active site of the enoyl-acyl carrier protein reductase enzyme (ENR), which is an essential enzyme in fatty acid synthesis in bacteria. By blocking the active site, Triclosan inhibits the enzyme, and therefore prevents the bacteria from synthesizing fatty acid, which is necessary for building cell membranes, for keeping the selective permeability and for reproducing. Triclosan is a very potent inhibitor of ENR, and only low concentrations are needed for powerful bactericidal action. Humans do not have this ENR enzyme. Two masterbatches with 10% triclosan on the base of polyethylene and polyethylene grafted with maleic anhydride (PE-g-MA) were prepared by an internal mixer. Then, these triclosan is an efficient antibacterial agent for medium-density polyethylene. Samples that had been cooled by quenching showed the best most antibacterial properties, while the samples that had been cooled isothermally showed the lowest antibacterial properties. On the other hand, the polyethylene which was grafted by maleic anhydride exhibited better antibacterial properties. .