The aim of this work was to study the preparation of carboxymethyl-chitosan nanoparticles and the mechanical performance of antibacterial paper. Carboxymethyl-chitosan nanoparticles were prepared using CaCl2 as ion crosslinking agent with ion-exchanging method, then antibacterial paper was prepared by coating the paper surface with nano-carboxymethyl-chitosan solution and its mechanical performance was studied. With increasing concentration of carboxymethyl-chitosan solution, the required concentration of the crosslinking agent calcium ion was also increased. The mechanical performance of antibacterial paper such as ring crush strength, bursting strength and tearing strength increased with the increasing nano-carboxymethyl-chitosan concentration coated, while the thickness showed no obvious difference, meeting the packaging requirement.By the coating of nano-carboxymethyl chitosan,some mechanical performance of antibacterial paper is better than the control paper， and it can meet the requirements of the mechanical properties of the antibacterial paper.