grafted galactose onto C6-OHfollowed by pegylation from C2-NH2group. They demonstrated nocytotoxicity of modified chitosan in HEK 293 kidney cancer cells.However, it was lack of data to verify the feasible application ofthis modified chitosan in drug and/or gene delivery.The present study was aimed to develop a hepatocyte-targetingnon-viral polymeric nano-carrier for gene delivery. Chitosan wasselected as the main polymer. In order to have specific liver tar-geting activity, an ASGPR recognized sugar molecule, galactose,was introduced into C6-OH of chitosan. The hydrophilic methoxypoly(ethylene glycol) (mPEG) or short chain PEG diacid (PEGd)was grafted onto galactosylated chitosan further through its C2-NH2position to increase solubility and stability of chitosan in vivo.The synthesized chitosan derivatives were characterized by FTIR,NMR and GPC, and the galactose, mPEG and PEGd graft contentswere determined. The galactosylated chitosan grafted with mPEGor PEGd was applied to complex with plasmid DNA, and the perfor-mance of polymer/DNA polyplex was characterized. The ability ofcondensing negatively charged plasmid DNA by modified chitosan,the stability of polymer/DNA polyplex and its cellular transfectionwere evaluated.