NOVELTY - Preparation of galactosamine and polydopamine modified nanoparticles includes dissolving polymer and hydrophobic medicine in organic solvent, stirring and adding polyethylene glycol 1000 succinate vitamin E water solution, stirring, removing volatile organic solvent, centrifuging, removing supernatant, washing initial polymer nanoparticles; suspending nanoparticles in tris buffer solution, adding hydrochloride, reacting, centrifuging, washing precipitate; dispersing polydopamine coated nanoparticles in weak alkali aqueous solution, adding galactosamine ligands, reacting, and centrifuging.    USE - Method for preparing galactosamine and polydopamine modified nanoparticles used for preparing medicine for treating malignant liver cancer (claimed).    ADVANTAGE - The method is simple, and has no pollution. The product has good biocompatibility and biodegradability, and therapeutic effect.    DETAILED DESCRIPTION - Preparation of galactosamine and polydopamine modified nanoparticles comprises weighing 100 mg polymer, and 2-20 mg hydrophobic medicine, dissolving in 8-10 ml organic solvent, stirring and adding 100 ml 0.3-10 mg/l polyethylene glycol 1000 succinate vitamin E water solution, stirring for 6-24 hours, removing volatile organic solvent under reduced pressure, centrifuging at 10000-20000 revolutions/minute (rpm) for 15-30 minutes, removing supernatant, washing initial polymer nanoparticles with deionized water to obtain carrier; suspending nanoparticles in 10 nM tris buffer solution having a pH of 8.5 at a ratio of 1-10 mg:1 ml, adding 0.2-1 mg/ml hydrochloride, reacting for 3-12 hours, centrifuging at 10000-20000 rpm for 15-30 minutes, collecting precipitate, washing with deionized water to obtain polydopamine coated nanoparticles; dispersing polydopamine coated nanoparticles in weak alkali aqueous solution having a pH of 8.5-12 at ratio of 1-10 mg:1 ml, adding 0.1-10 mg/ml galactosamine liver-targeting ligands, reacting for 1-3 hours, centrifuging at 10000-20000 rpm for 15-30 minutes, collecting nanoparticles, washing with deionized water, and freeze-drying.