Polypropylene (PP) films were irradiated with corona discharge then dipped into acidic solutions of chitosan extracted from different sources. The films were examined as for their antifungal and antibacterial properties. Carboxymethyl chitosan and carboxymethyl chitin were found also to adhere to these corona treated PP films. The antifungal and antibacterial properties of these derivatives were also examined and found to be even superior to the chitosan itself. Chitosan forms complex compounds with pectin and this property was used to build up a stable multilayered structure on the PP film surfaces to produce a much better antimicrobial films which can be used to fabricate excellent packaging materials for post-harvest crop protection.