Abstract: AimTo investigate the paclitaxel-loaded nanoparticles of poly(ethylene glycol)-b-poly(D,L-lactic acid) amphiphilic diblock copolymer (PMT). MethodsPMT was prepared by solid dispersion technique. The average size and size distribution were determined by dynamic light scattering (DLS). The morphology was characterized by transmission electron microscopy (TEM) and ¹HNMR. The influences of the copolymer molecular weight and the paclitaxel-fed amount on PMT were studied. Therapeutic effect of PMT was studied on Kunming mice liver cancer H22. ResultsPMT showed nanometer size and spherical morphology with core and shell. The sizes of PMT increased with increasing the molecular weight of the hydrophobic segment in PEDLLA or increasing the drug-loaded amount. The tumour inhibiting effect of PMT was similar with that of Taxol. ConclusionIt will provide an experiment basis for the development of new kind of intravenous administration of paclitaxel.