Abstract: Taking the drug-loading and entrapment efficiency as assessment indexes,we determined the process to load paclitaxel (PTX) using glycyrrhetinic acid-modified hyaluronic acid (GA-HA) nanoparticles by the single factor method.GA-HA nanoparticles could encapsulate PTX up to (31.2±0.8)%,with entrapment efficiency of (90.3±1.6)% .The particle size of PTX-loaded nanoparticles negatively charged was (321.2±8.2) nm.In vitro release of drugs from nanoparticles was investigated.Sustainable release of PTX/GA-HA nanoparticles was faster in acidic environment.From the cytotoxicity test,it was found that PTX/GA-HA nanoparticles exhibited strong cytotoxicity to many cells,especially in hepatoma cells.The cellular uptake of GA-HA nanoparticles was also investigated.When cancer cells over-expressing CD44 (the receptor for HA) were treated with fluorescently labeled GA-HA nanoparticles,stronger fluorescence signals were observed compared to free FITC.These results suggest that GA-HA nanoparticles have the potential as a novel polymer carrier of drugs for cancer therapy.