CS-PAA/Zn2+ composite network hydrogels were prepared by UV illumination method using chitosan (CS) and acrylic acid (AA) as raw materials and Zn2+ with bactericidal effect as ligand ion. The effects of the material ratio of AA to chitosan and the addition of Zn2+ solution on the structural morphology and properties of CS-PAA/Zn2+ were investigated by FTIR, XRD, SEM, dissolution and tensile tests, as well as cellular activity and antimicrobial tests. The results showed that the CS-PAA/Zn2+ composite network hydrogel was formed by using the CS chain as the main chain and -NH2 as the first site to cross-link the shorter PAA short chain, which reduces the generation of PAA and forms the first network; the carboxyl group on the short chain of PAA was used as the second site, which utilizes the dynamic metal coordination effect of Zn2+ to form the second network. CS-PAA/ Zn2+ composite network hydrogel exists a relatively uniform and flat outer structure and an inner structure rich in piping spaces and pores; when 1 g chitosan was used as the raw material, n(AA):n(-NH2 on CS) = 1:1, and 0.01 mol/L Zn2+ solution was added in an amount of 4.0 mL, the prepared CS-PAA/Zn2+ composite network hydrogel had the strongest swelling and stretching ability, with the maximum swelling degree of 87.2 and elongation at break of 331.265% in pH = 1 solution, while maintaining a good cellular (MDA-MB-231 cells) activity and antibacterial (Escherichia coli) properties. And the gel had low cytotoxicity, cell proliferation rate of 509%, good antimicrobial properties, and the diameter of the inhibition circle reached 5 mm after the addition of Zn2+.